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is the Journal of the Biological Society, Victoria University of Wellington, New Zealand, and is published three times a year, with the financial assistance of the University Publications fund.
Tuatara aims at stimulating and extending the interest of secondary school pupils, university students and amateur naturalists in the natural sciences, and at the same time presenting reviews of value to scientists showing the present applications and future scope of biological research. Articles and reviews of a suitable standard are solicited. Contributors are requested to limit lists of ‘Literature Cited’ to the more important references.
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In presenting a symposium of three integrated contributions the present issue of Tuatara is a substantial addition to the literature of the New Zealand fauna, for every amphibian known from this country is here figured and described by those best qualified to do so. To Richard Barwick, who painted the colour plate, and to the other authorities who have contributed, we are greatly indebted, as also to Mr. W. P. Carman for his care in the accurate reproduction of the plate. The cost of the colour printing has been met by a grant of £105 from the Publication Fund of the Victoria University of Wellington, and one of £25 by the Department of Internal Affairs. We are grateful to the donors for their practical expression of confidence.
The accompanying full-colour plate shows the six species of frogs found in New Zealand. Although single species have previously been illustrated in colour, e.g. Leiopelma hamiltoni in McCulloch (1919), no one illustration showing all the known species has yet appeared.
In the illustration the frogs are drawn to show as clearly as possible the main distinguishing features, even if this results in slightly unnatural postures. In some cases a hind leg is arranged to display either the intense colour of the thigh, normally concealed when the frog is crouching, or the nature of the webbing between the toes.
Except where otherwise stated below, the illustrations are of recently-caught, live specimens. This is a necessary precaution, for in captivity frogs may undergo colour changes and lose condition, becoming dull and drab coloured. The water-colour painting here is an attempt to illustrate as nearly as possible typical specimens of each species when they have
Some frogs have an extremely wide range of colour forms; of the indigenous New Zealand frogs this applies particularly to Leiopelma archeyi (Stephenson and Stephenson, 1957, p. 875). Individuals of the other species are more constant in their colour form but may vary from the illustrated example in that their overall colouring becomes darker, even to the extent that the pattern of colours present in the light phase is obscured (e.g. Hyla aurea). To achieve standard conditions for the purpose of the illustrations, each live frog was placed on a light background. This ensured that the animal maintained the lightest possible colour phase.
The three species of the genus Hyla, introduced into New Zealand from Australia, displayed considerable ability in changing their body colouration. Hyla aurea when removed from a dark cage in the morning was blackish-green, often with all colour pattern totally obscured. After thirty minutes on a light-coloured background the frog assumed the intense colours shown. Against a dark background Hyla ewingi tended to assume an overall rich brown colour, similar to that seen mid-dorsally in the frog illustrated. The brown faded to a dusky grey, particularly on the sides of the body, after a period in bright daylight.
In contrast, the colouration of Hyla coerulea changed little, the animal becoming a slightly darker green in low light intensities, with little change or loss of body markings.
Frogs of the New Zealand indigenous genus Leiopelma showed no obvious colour changes in comparison to hylids. In no case did the body pattern become obscured; but the frogs did become slightly darker coloured when placed in a dark container. Only one marked change of colour was observed when Leiopelma hamiltoni showed small patches of light green amongst the overall golden brown of the flanks; this change occurred after the frog had been exposed to bright sunlight for about two hours. The green patches on the body and legs of Leiopelma archeyi were seen to become more intense and sharply defined in intense light.
It was noted that typical stances are assumed by the six species of frogs when at rest, and some comparisons can be made. Hyla aurea tends to sit with its hind legs closely adpressed to the body, and the forelimbs extended so that the head is raised high. Hyla coerulea often assumes a crouching posture, all four limbs closely pressed against its body, and with hands and feet tucked underneath chin and stomach. When inside its terrarium, H. coerulea favoured a resting position several inches above the floor, in the right angle formed by two vertical sheets of glass. The large expansions of the tips of the digits and toes of this species allow it to walk with ease up smooth vertical surfaces, even glass. H. ewingi typically assumes one of two positions. In the crouching stance the back is flattened, the limbs are held close to the body, and the fingers and toes are tucked in, so that the animal has a rather pear-shaped outline. In the ‘alert’ position H. ewingi resembles H. aurea except that there is a distinct tendency for the forelimbs to be rotated until the digits lie beneath the body.
The attitudes at rest of the three species of Leiopelma vary little from those shown in the illustrations, except that I have lowered and slightly rotated the metatarsus and pes to display the nature of the toe-webbing clearly.
In movement H. ewingi displays the characteristic walk of frogs of the mainly arboreal genus Hyla. H. ewingi walks with its body elevated high from the ground and the hind legs extended well behind the body, almost as if they follow unwillingly the progression of the rest of the animal. The walk of H. coerulea is similar but less ungainly in character, probably because the species is stouter limbed. H. aurea is less typical of the genus, for its walk resembles that of the leiopelmid frogs, being confined to short hind limb movements without rearward extension of the hind limbs, the body being held close to the ground.
Tonic immobility is shown well by the leiopelmid frogs. This state can be induced by gently placing a frog on its back so that its limbs are clear of the ground beneath. After a few seconds when the animal has become quiet and ceases to struggle, one's hand may be carefully withdrawn. A frog so positioned may remain immobile for many minutes provided it is not touched or disturbed in any way. Such tonic immobility is often of use when making measurements or noting the colour of the ventral surfaces of a frog, since it allows the animal to be studied at leisure.
I wish to thank: Mr. L. Gurr, Massey College, and Mr. A. Gates, Orua Downs, for assistance in obtaining Hyla aurea and H. ewingi; the Robb family, Maud Island, for their hospitality and assistance in the field while collecting Leiopelma hamiltoni; Mr. D. S. Boswell, Coromandel, for his great assistance in the collection of Leiopelma archeyi and L. hochstetteri; Dr. Hyla coerulea; the Department of Internal Affairs for permission to procure and retain for the Department of Zoology, Victoria University of Wellington, one example of each of the Leiopelma species; and Professor
Although presumably the ancestors of the native frogs reached New Zealand during the Cretaceous period, a record of their presence was not made until the early gold-mining days of the mid-nineteenth century. While Leiopelma hochstetteri.
A few years later, the Austrian naturalist, Hochstetter, collected frogs of the same type from the Coromandel peninsula during the voyage of the frigate Novara. In 1861 these specimens were described and named after Hochstetter by Fitzinger. Subsequently a fuller description and a change in family classification were made by Steindachner (1869), whose account was translated by Hutton in 1879.
In 1919, a second species, found on Stephens Island in Cook Strait, was named Liopelma hamiltoni by McCulloch in honour of its discoverer.
Although a number of early records of the finding of small brown and green frogs high on the mountain ridges of the Coromandel peninsula are available (McLaren, 1898; Smith, 1921; Archey, 1922; Graham, 1924), these frogs were not recognised as belonging to a new species until 1942. In that year Leiopelma archeyi in honour of Dr.
In spite of a time lapse of over 100 years since their first discovery, many problems concerning the New Zealand frogs still remain to be solved. The following account attempts to indicate some of these.
Early classifications of the frogs into families showed considerable variation. In 1924, however, G. K. Noble, who had recognised the affinities of Leiopelma Fitzinger with Ascaphus Stejneger of North America, placed the two genera in a new family, the Liopelmidae. In 1931 he placed this family in a separate sub-order, the AMPHICOELA, in recognition of the fact that the two genera are more primitive, as far as certain important anatomical features are concerned, than any other known anurans. The name of the sub-order refers to the amphicoelous condition of the vertebrae, the term usually indicating that the centra are biconcave and the intervertebral cartilage undivided. That this term is inadequate to convey fully the vertebral condition of Ascaphus and Leiopelma has recently been pointed out by Ritland (1955), but as a basis of classification serving to separate the two genera from other living frogs and toads it still fulfils its purpose.
Another primitive characteristic distinguishing Leiopelma and Ascaphus from other adult anurans is the presence of two tail-wagging muscles, though neither genus possesses a tail in the adult stage. In addition, these two genera have nine presacral vertebrae, one more than the maximum number recorded for any other living frog or toad.
The characters mentioned above are not the only ones illustrating the essentially primitive nature of Leiopelma and Ascaphus but most of the others are shared by some members of other anuran families. As might be expected, each genus has also developed certain specialised, adaptive characters but sometimes controversy exists about whether a particular character is to be regarded as primitive or specialised. For example, many zoologists would class the absence of certain middle ear structures in Leiopelma and Ascaphus as representing a secondary loss of a specialised nature. This is by no means necessarily so, as N. G. Stephenson (1951 b, pp. 243-7) has already pointed out. On the other hand, the unique intromittent organ of Ascaphus, developed as an extension of the cloaca, is clearly of a specialised nature (Noble, 1931). The tadpoles of Ascaphus have an equally unique arrangement of tooth ridges or plates. These features appear to be of particular value in the swift-flowing mountain streams frequented by the genus, the arrangement of larval teeth assisting in attachment and the erectile cloaca of the adult male ensuring adequate fertilisation.
Of the three species of Leiopelma, L. hochstetteri has the greatest external resemblance to Ascaphus, but the methods of development of the two genera are quite different. Ascaphus has a free-swimming tadpole stage, while the entire development of Leiopelma, at least in the two species of which eggs have been found, is intracapsular, the embryo developing entirely within a gelatinous capsule formed from the original egg. It hatches as a tailed froglet with legs, the tail being resorbed within a comparatively short time.
In 1942, Turbott pointed out that Fitzinger's original spelling of the generic name Leiopelma had been altered by Gunther in 1868 to Liopelma and that the alteration had been copied by later authors. Turbott emphasised that the original spelling used by Fitzinger should be retained and that it should also be extended to the family name (i.e. Leiopelmidae instead of Noble's Liopelmidae). The family name itself is a matter of some contention. In 1923, Fejervary proposed the name Ascaphidae for the family containing the genus Ascaphus. This predated Noble's family Liopelmidae (1924), which was designed to include both Liopelma Gunther 1868 laps. cal. = Leiopelma Fitzinger 1861 and Ascaphus Stejneger 1897. Noble chose the oldest generic name as the basis for his family name. N. G. Stephenson pointed out (1951 b) that if this name is to be used it should more correctly be Leiopelmatidae.
The oldest generic name is not, however, a necessary requirement of taxonomic procedure for the formation of a family name, so that the name Ascaphidae does have priority over Liopelmidae or Leiopelmatidae. It also has the advantage of avoiding the errors of formation and of spelling of Noble's family name. As the name Ascaphidae is already in fairly wide use, it seems better to conform to this terminology as long as Ascaphus and Leiopelma remain together in one family.
At the present time, the genus Leiopelma Fitzinger is considered to include three species; Leiopelma hochstetteri Fitzinger, L, hamiltoni McCulloch and L. archeyi Turbott. In compiling the following key to their identification, reference has, of course, been made to descriptions and keys provided by earlier workers including Fitzinger (1861), Steindachner (1869), McCulloch (1919) and Turbott (1942).
Tympanic membrane, eustachian tubes and vocal sacs absent. Teeth present in upper jaw. Teeth on prevomers in two straight or slightly oblique patches situated between the choanae and towards or slightly behind the posterior margins of the latters. Fingers free. A whitish metacarpal tubercule present on each side of palms of hands. A smaller, whitish, inner metatarsal tubercle present on sole of foot. Outer metatarsal tubercle absent. More or less distinct oblique black bands on dorsal surface of limbs. Under-surface of body mottled greyish-brown.
Several points in connexion with this key require further elaboration. The absence of a tympanic membrane (a round patch, corresponding to an eardrum, found behind and below the eye in many frogs) in Leiopelma should make this genus easy to distinguish in the field from any of the species of Hyla now found in New Zealand.
The parotoid glands of L. archeyi and L. hamiltoni form conspicuous, ridge-like swellings behind the eye. Each consists of a double row of round to oval, yellowish glands lying beneath the surface of the skin and opening through it. They produce a white secretion. Nothing is known of its effect on possible predators of Leiopelma, but in some toads the secretion of the parotoids is known to be highly toxic. Glandular ridges and isolated patches of glands also occur elsewhere on the body and limbs. The extent of these appears to be variable within each species.
Although the maximum body length of L. archeyi has been given as 41 mm., this measurement has been recorded only once for the species. Measurements up to 39 mm. are not unusual from areas on the Tokatea Ridge. The maximum length so far recorded for L. hamiltoni is 47 mm. L. hochstetteri appears to conform to the body length range of L. hamiltoni.
Where the colour pattern is described above as being ‘variable’, this means variable throughout the species, not in a particular individual. Frogs kept in captivity for two years maintained constant, individual colour patterns and could readily be recognised by these.
In a recent publication (Stephenson and Stephenson, 1957, p. 869), McCulloch's original specimen of L. hamiltoni was described as being ‘patterned in green and brown‘. It is difficult to say just how this misconception arose. But further checking of McCulloch's description has shown clearly that the frog in question was light brown. Of the specimens of L. hamiltoni from Maud Island described by Mr. Bell all were either light or dark brown.
Leiopelma hochstetteri has been recorded from a number of localities in the North Island. These include Warkworth (forty miles north of Auckland), several places in the Waitakere Ranges, the Coromandel Peninsula and areas along the north-east coast south of the Coromandel Peninsula.
L. archeyi is known only from the Coromandel Peninsula, where it may either occur alone, or may closely overlap the range of L. hochstetteri. In the latter case it is a common occurrence to find members of both species under the same log or stone. The best known areas for L. archeyi are probably Mt.
Until very recently, Leiopelma hamiltoni was known only from Stephens Is. in Cook Strait and there from a very restricted area. This consisted of a barren boulder bank at the top of the island at a height of about a thousand feet. So localised was the spot and so rigorous the conditions that it was thought for some years that the frogs had became extinct. A party led in 1950 by Mr. L. hamiltoni McCulloch, or should be regarded as members of a new species. These frogs have been carefully examined and measured externally and have been studied internally by means of alizarin transparencies and by sectioning of certain regions. In addition, Mr. Bell made a series of detailed measurements of nineteen frogs on Maud Island. Against these were checked measurements of two specimens of L. hamiltoni, one from the Canterbury Museum and one from the Dominion Museum. As a result of these anatomical and statistical investigations it seems better not to try to assign any difference in specific status at present to the Stephens Is. and Maud Is. frogs.
The position of the nostrils relative to the tip of the snout and to thieve was previously thought to be of use in distinguishing L. archeyi from L. hamiltoni. McCulloch (1919) described the nostril of L. hamiltoni as being midway between the tip of the snout and the eye. In L. archeyi, as described by Turbott (1942), the nostril is nearer to the eye than to the tip of the snout. This condition was confirmed by a lengthy series of measurements carried out by the writer on Mt. L. archeyi. Most of the others measured by Mr. Bell showed the same condition but in two the nostril was equidistant between the tip of the snout and the eye. Measurements of two specimens of the Stephens Is. frog, kindly carried out by Mr. McCann of the Dominion Museum and Mr. Turbott of the Canterbury Museum, indicated that in one animal the nostrils were: equidistant and in the other they were nearer to the eye. These facts, together with the difficulty of carrying out the particular measurement satisfactorily in the field and the small difference involved (usually only about 1 mm.) suggests that it would be highly undesirable to base a specific diagnosis on this character alone. In any case, L. hamiltoni, whether from Maud Is. or Stephens Is., appears to show some variation in this feature.
A comparative anatomical survey of the three species recently completed by the writer (L. archeyi has the essential skeletal characteristics of an immature or juvenile L. hamiltoni, but that it becomes sexually mature while still in this condition. This phenomenon of heterochrony, implying a change along the time axis of development of an organism, is well known in Amphibia, extreme examples being furnished by cases of neoteny among certain newts. In these cases the newts concerned remain as permanent larvae which become sexually reproductive. Heterochrony can obviously be a factor of importance in speciation and general evolution.
Because of the facts stated above, differentiating between young specimens of L. hamiltoni and mature brown specimens of L. archeyi on
Certain features in connection with the life history of Leiopelma have not been recorded. In no species has the actual process of mating been recorded. Almost certainly it occurs at night, for during the day the frogs shelter under stones, logs or in clumps of vegetation. They normally become active only in the dark. This is also the typical, although not invariable pattern of the frogs when kept in captivity.
Leiopelma archeyi lays clusters of two to eight or more eggs, each surrounded by a gelatinous capsule. The eggs are heavily yolked, unpigmented and measure 4 mm. to 5 mm. in diameter. They are found in or under rotting logs, or in the soft decaying wood of damp tree stumps. The exact time of egg laying or of fertilisation is uncertain but well developed embryos can be found in the capsules in November and December. For an account of the development of Leiopelma archeyi, refer to Archey (1922), and to N. G. Stephenson (1951a). When the tailed froglets are ready to hatch, they pierce the capsule with rotating muscular movements of their tails, helped by a glandular secretion. An interesting and important fact, discovered by Archey and confirmed more fuy by N. G. Stephenson, is that if the embryos are released from their capsules into water they will continue to develop, indicating that the intracapsular mode of development is perhaps less specialised than is generally thought.
Several times, male frogs have been found sitting over clusters of eggs. Their exact function is not known. Possibly, although this seems unlikely, they are exhibiting brooding tendencies known in some amphibia. Possibly they are ensuring external fertilisation. Supporting the latter view is the fact that they have been found over clusters of eggs at a relatively early stage in development and that it is quite common to find infertile eggs in a cluster. Yet another possibility is that the urinary excretion of the frogs provides additional moisture for the eggs.
Until 1949, nothing was known of the egg-laying or breeding habits of Leiopelma hochstetteri. Then, following a discovery made by Mr. Gittos of Warkworth, Mr. Turbott was able to collect eggs buried in wet mud of a seepage above a stream. L. hochstetteri also has an intracapsular development in which the embryos do not have a free-living tadpole stage, but hatch from the egg as tailed froglets.
Nothing is at present known about the mating or development of Leiopelma hamiltoni. Presumably it follows the general L. archeyi pattern but the finding of the first cluster of eggs will be an interesting discovery.
Although Leiopelma hochstetteri has primarly been regarded as a stream-dwelling frog, it has often been found under logs or stones well away from surface water. This is particularly evident in patches of bush along the Tokatea Ridge in the Coromandel Peninsula. In this region, as has already been mentioned, L. hochstetteri and L. archeyi overlap in range and both species may be found together under logs or stones. It was at
L. archeyi. Further examination showed that it had a well-defined half-web and in most other characteristics could be regarded as a member of the species L. hochstetteri. A glandular ridge was present behind the eye but it did not have the same degree of development as the normal parotoid of L. archeyi. No other instance of green coloration in L. hochstetteri has been recorded. One of several possible suggestions is that some degree of interbreeding may be occurring between L. archeyi and L. hochstetteri on the Tokatea Ridge, but much more information is needed on this point.
Although the results of a statistical study in progress are not yet available, some indication is seen that an overall size difference, possibly indicating subspeciation, exists between populations of L. archeyi on Mt.
Obviously, much still remains to be learnt about these interesting, rare and primitive frogs. An accurate account of the process of mating and egg-laying would be of particular interest. It is to be hoped that any observer of amplexus (pairing) will record it by means of photographs if possible or by an accurate sketch. No one has yet recorded whether the embrace is in the pectoral or the pelvic region. The latter type is found in Ascaphus and other primitive genera and could be expected in Leiopelma.
Whatever the gaps in our knowledge, it is essential that any observations of the native frogs must not be carried out at the expense of the animals themselves. The genus is protected by law and no specimens may be collected without the permission of the Hon. Minister for Internal Affairs. The frogs are highly susceptible to drying and must be protected from this danger if they are being handled. Logs and stones must be replaced in their exact positions and vegetation must not be unnecessarily disturbed. It should be emphasised, however, that some of the important discoveries connected with Leiopelma were not made initially by trained zoologists and that this could, through chance, be the case again.
Among the animals which have been successfully introduced to New Zealand are three species of Australian frogs. Attempts have also been made to introduce a fourth frog (Rana temporaria) and a toad (Bufo vulgaris) from Europe, but without success. It might well be asked why anyone should wish to have these animals in New Zealand, for, generally speaking, they are looked upon as loathsome. The reasons for their introduction fall into two categories: (a) their usefulness to man, and, (b) as possible ‘ reminders ’ of the homeland of the colonists.
New Zealand has its indigenous frogs, but they are comparatively small and rare and accordingly need protection. Incidinetally, the existence of the indigenous species was barely known at the time the exotic species were introduced. Frogs and toads are needed in the pursuit of academic studies and biological research, and for certain medical tests. For these purposes a call on the indigenous, slow-breeding species would soon write ‘finis’ to the existence of these unique creatures. Under the circumstances suitable substitutes had to be imported which would not have too great an impact on the natural fauna. This was achieved with a fair amount of success, resulting in the acclimatisation of three species of the genus Hyla from Australia. In addition, a supply of toads (Bufo) required for medical tests is maintained by some hospitals by periodical consignments from Fiji and some of the other Pacific Islands. Toads are occasionally accidentally imported in cargoes of fruit but, as far as I am aware, no toads appear to have established themselves in a feral state.
The three species that were successfully introduced are Hyla aurea, the Green Frog; H. ewingi, the Brown Tree Frog or Whistling Frog; and H. caerulea, the Great Green Tree Frog. Of these Hyla aurea is common and widespread. H. ewingi is common on the west coast of the South Island and Southland, while in recent years it was successfully introduced into the North Island. H. caerulea is present in parts of the North Island, but has rarely been found.
The following account is an attempt to cover in brief form the main aspects of the biology and natural history of the introduced frogs. It includes also a description of each species, and a literature list giving the main items of the synonymy and New Zealand references.
The Hylidae includes the true tree frogs and may be described as bufonids with intercalary cartilages and usually with dilated sacral diaophyses. There are sixteen genera of hylids and these are placed in two subfamilies. All, except Hyla, are confined to the New World. Two genera, Hylella and Nyctimystes have been described from East Indian and Australian regions, but these are scarcely distinct from the genus Hyla. Hyla is almost cosmopolitan in its distribution, except for an hiatus in the Indomalayan (including Borneo), Polynesian. Ethiopian and Madagascan regions. One species, perhaps erroneously, has been recorded from the Gulf of Guinea, and two have been recorded from Java. Hylids may be arboreal, terrestrial or aquatic and some are fossorial.
The Hylinae include hylids which lay their eggs in or near water; possess dilated sacral diapophyses and terminal claw- or T-shaped phalanges. Usually twelve genera are recognised but this number may be increased to fifteen according to some authorities. Many of the hylids closely resemble members of the sub-order, Diplasiocoela, particularly of the genus Rana.
Pupil horizontal; tongue entire or slightly nicked, adherent or more or less free behind. Vomerine teeth present. Tympanum distinct or hidden. Fingers free or slightly webbed; toes webbed, the tips dilated into larger or smaller discs. Outer metatarsals united or slightly separated. Omosternum cartilaginous; sternum a cartilaginous plate. Diapophyses of sacral vertebrae more or less dilated. (After Boulenger, 1882.)
Plate I, figs. 1-2; text-fig. 1, fig. 1
Rana aurea Lesson, 1830. Voy. ‘Coquille’, Zool., p. 60, pl. 7, fig. 2 (Syst.).
New Zealand references.Hyla aurea Guenther, 1858. Cat. Tailless Batr. Brit. Mus., p. 114 (Syst.); Steindachner, 1869. ‘Novara’ Amphib., p. 161 (Syst.); Boulenger, 1882. Cat. Batr. Sal. s. Ecaud. Brit. Mus., 2nd Edit. p. 140 (Syst.); Fletcher, 1889. Proc. Linn. Soc. N.S.W. 2nd ser. 4: 384 (Breeding); Gadow, 1901. Amphib.
Habit raniform. Tongue suboval, nicked and free behind. Vomerine teeth between the choanae, in two slightly oblique series convergent posteriorly. Head as long as broad, or a little longer than broad, resembling in shape that of Rana esculenta; snout longer than the diameter of the eye: canthus rostralis moderately distinct: loreal region slightly concave; interorbital space narrower than the upper eyelid. Fingers free; no distinct rudiment of pollex; toes entirely webbed, or nearly so; digital discs small, about half the diameter of the tympanum; subarticular tubercles moderate; a distinct fold along the inner edge of the tarsus. The tbio-tarsal joint of the hindlimb breaches the eye, occasionally less or slightly beyond. Skin smooth or warty above, granulate beneath; a more or less distinct glandular lateral fold. Male with two internal vocal sacs. Brown rugosities on inner side of first finger developed during the breeding season. (After Boulenger, 1882.)
Adult males are about two-thirds smaller than adult females; females up to 92 mm.
Male: Snout to vent 62 mm.; hindleg 91 mm.; foot 42 mm.; longest toe 26 mm.; snout to nostril 4.5 mm.; snout to tympanum 15 mm.; snout to eye 9 mm.; eye 6 mm.; tympanum 4 mm.; distance between eyes (anterior corner) 7 mm.; testes (breeding) 10 by 2 mm. (Dom. Mus. 83.)
Female: Snout to vent 92 mm.; hindleg 227 mm.; foot 69 mm.; longest toe 36 mm.; snout to nostril 7 mm.; snout to tympanum 22 mm.; snout to eye 13 mm.; eye 9 mm.; tympanum 7 mm.; distance between eyes 13 mm. (Dom. Mus. 84.) Ova almost mature.
The colour and colour pattern of this species is very variable and is largely dependent on its immediate surroundings. Commonly it is a brilliant pea-green above and purplish beneath with longitudinal bands of golden yellow on the back; a black dorso-lateral line is often present. The forelegs are green mottled above with yellow, the hind legs are bluer green with
Australia, widely distributed through the greater part of the continent except in the desert regions. Introduced into New Zealand and is now found in most streams and pools throughout the Dominion and on some of the off-shore islands.
In the tadpole stage frogs are generally herbivorous, rasping off algae and other vegetable matter with the beak and the labial horny teeth. They will also feed on animal tissue in the same way. In the adult stage the diet is entirely carnivorous. They will take almost any animal life that they can overpower and conveniently swallow, from insects to lizards and even their own species when opportunity arises. Lengthy or large objects are ‘shovelled’ into the mouth by the alternate use of the ‘hands’.
The enemies of frogs are numerous. As eggs and tadpoles they are devoured by aquatic insect larvae, fish and lacustrine birds. As adults they are eaten by lacustrine birds such as herons and bitterns, etc., while wekas, pukekos and kingfishers possibly account for a number also. On land some of the smaller mammals will also eat frogs when available.
Normally females are voiceless for they are not provided with vocal sacs, but they are capable of emitting short grunts by way of protest when handled, or a piercing shriek when caught by an enemy. The male of H. aurea is provided with a pair of internal vocal sacs which normally come into play during the breeding season. The voice is a loud castanet-like call which can be heard over a considerable distance. In concert the call has been described as deafening.
H. aurea is usually found in the vicinity of streams, lakes and pools. Garden ponds have a special attraction for them, and during the breeding season they will congregate in large numbers in such places.
This species is essentially terrestrial and aquatic. Under cover of darkness or in dull weather it will wander far and wide. During the day it remains in the vicinity of water and may be seen sitting on floating leaves and branches where it can quickly return to the water and submerge on the slightest sign of danger.
A frog's life may be divided into two periods: one of active feeding, and the other of rest or hibernation during the winter. Between the two a short breeding period intervenes during which the eggs are laid and left to their fate.
Undoubtedly, the breeding and developmental cycles may be accelerated or retarded according to the locality and the prevalent climatic conditions. During the active period of vigorous feeding, frogs accumulate sufficient reserve fat, in special fat-bodies, to tide them over the winter and to build up the gonads in readiness for the next breeding cycle. The gonads develop considerably during the winter sleep and after breeding is over they become greatly reduced.
In the spring the frogs emerge from hibernation looking none the worse for their long fast. Normally, the first impulse on emergence is to breed. A large female taken on August 29, 1952, near the
When ready to mate and spawn the pairs engage in amplexus, the male clasping the female dorsally in a firm embrace behind the armpits. The pair remain in this embrace till egg-laying is completed. During amplexus the male exerts considerable pressure, thus assisting in the passage of the ova to the exterior. At the same time the male exudes the spermatoza into the water, as fertilisation is external. The male also’ ‘paddles’ his hind legs from time to time as though he were making an effort to maintain his position, but this action, I believe, is partly to stimulate the female and partly to churn up the surrounding water to disseminate the products of both sexes and enhance the chances of fertilisation. With the decrease of the ova the male's grasp moves back on the abdomen of his mate till finally amplexus ceases.
The ‘puddling’ action of the male during amplexus has been described as ‘then kicking the female vigorously in the ribs he induces her ova into the water’. (Martin, 1947.) This figurative expression is partly true, but contains an inaccuracy insomuch that frogs possess no ribs.
After deposition of the eggs in water they hatch in a few hours (or perhaps a few days) according to the temperature of the water. The duration of the tadpole stage and metamorphosis, as far as I am aware, has not been recorded for this species. However, as I have seen metamorphosis completed (around Wellington) by summer, it seems reasonable to suspect that it lasts about two to three months. Undoubtedly, the period varies according to locality, temperature and food supply. Nevertheless, it seems almost certain that metamorphosis must be completed before the onset of winter. Under normal conditions it is doubtful whether the tadpoles, not possessing a great surplus of reserve fat, could survive a period of hibernation.
Thomson (1926) states: ‘Tadpoles which are unable to leave the water in which they have been born— as, for instance, those confined in
The specific determination of tadpoles is difficult as they present few reliable morphological characters. Optimum size, i.e. the linear dimensions attained just before the completion of metamorphosis, is a good character but allowance must be made for limited variation. The structure and configuration of the lips and the arrangement of the horny teeth in relation to the beak are considered of systematic value, but, again, due allowance must be made for slight variation according to the age of the individual tadpole and damage to the series.
A tadpole collected at Palmerston North in March, 1960, with the hindlimbs just appearing measures, in total length, 60 mm. (tail 37 mm. by 15 mm. at its deepest point, including membrane). Another, taken at the same time as the above, with the hindlimbs fully developed, measures 70 mm. (tail 44m., by 15 mm. at the deepest point); hindlimb 26 mm.; foot 12 mm.; longest toe 5 mm. This specimen probably represents the optimum size attained by the tadpoles of H. aurea before assuming the frog stage.
The lips of both specimens are papillate (text-fig. I, fig. 1), the second showing a certain amount of reduction at this stage. There are two series of horny teeth above the beak and three below; the uppermost of the lower series is interrupted at the centre by a short interval.
The introduction of H. aurea to New Zealand has been the most successful of all three species. Probably the first attempt to introduce it was that of the Auckland Acclimatisation Society which, in 1867, introduced two specimens and augmented its efforts in the following year by several more consignments from Sydney. Australia. These frogs soon established themselves.
About the same time as H. aurea was introduced into the North Island, the Southland Acclimatisation Society, in 1868, introduced some spawn from Tasmania(?), but this attempt evidently did not meet with success, for no signs of the frogs were seen in 1890. In 1888, some of the successful ‘northern colonists’ were transported from Napier to Southland and liberated in a marsh, but evidently the new environment did not suit them and the attempt failed once more. However, not discouraged by failure, the importations were repeated from the North Island to the areas of Otago and Southland and eventually proved successful. Today H. aurea is common in suitable localities throughout the Dominion. It serves an useful role in biological studies in this country and an addition to the menu of some of the local fauna.
Text-fig. I, fig. 2
Hyla ewingii Dumeril and Bibron, 1841. Erp. Gen., 8: 597 (Syst.).
Hyla ewingi Steindachner, 1869. ‘Novara’ Amphib., p. 62 (Syst.); Boulenger, 1882. Cat. Batr. Sal. s. Ecaud. Brit. Mus., p. 406 (Syst.); Fletcher, 1889.
Proc. Linn. Soc. N.S.W., 2nd ser., 4: 383 (Breeding); Gadow, 1901. Amphib. and Rept. Cambr. Nat. Hist. Ser., 8: 201 (Breeding); Marriner, New Zealand references.
Tongue heart-shaped, free behind. Vomerine teeth in two small transverse or slightly oblique series between the choanae. Head moderate, a little broader than long; snout rounded, as long as the diameter of the eye; canthus rostralis distinct; loreal region not or but slightly concave; interorbital space as broad as, or a little broader than, the upper eyelid; tympanum distinct, half or three-fifths the diameter of the eye. Fingers with a slight rudiment of web; no distinct rudiment of pollex; toes two-thirds webbed; digital discs smaller than the tympanum; subarticular tubercles moderate; a distinct fold along the inner edge of the tarsus; tibio-tarsal articulation reaches the tympanum or eye. Upper surface smooth or with small scattered tubercles; lower surfaces granulate; a fold above the tympanum. Male with an external subgular vocal sac; during the breeding season the inner side of the first finger is covered with blackish rugosities. (After Boulenger, 1882.)
The males are considerably smaller than the females which may reach 45 mm.
Male: Snout to vent 34 mm.; hind leg 50 mm.; foot 22 mm.; longest toe 13 mm.; snout to nostril 2 mm.; snout to tympanum 7 mm.; snout to eye 4 mm.; eye 3 mm.; tympanum 2.5 mm.; distance between eyes (anterior angle) 5 mm.; testes 5 by 1 mm. (breeding), (Dom. Mus. 51).
Female: Snout to vent 43 mm.; hind leg 68 mm.; foot 30 mm.; longest toe 19 mm.; snout to nostril 2 mm.; snout to tympanum 10 mm.; snout to eye 6 mm.; eye 4 mm.; tympanum 3 mm.; distance between eyes (anterior angle) 7 mm.
The general colouring varies considerably from a uniform dark brown with or without markings to almost creamy white without markings or with minute blackish flecks. In some specimens a dark brown pattern extends from the snout down either side of the vertebral column to the vent, the flanks being lighter. A characteristic blackish band stretches from the nostril through the eye (broader behind the eye) to the insertion of the forelimb or slightly beyond; another dark streak margins the uper jaw as far as the angle of the gape; between the two dark bands the colour is a greyish-white. Eye brown, lighter above; pupil oval, black (the
Australia: It is spread over south-west and south Australia, New South Wales, Victoria and Tasmania.
The males are provided with vocal sacs which produce a shrill piping sound, hence the popular name, Whistling Frog.
The general habitat of this species appears to be bushclad country of a swampy nature where the humidity and herbage afford it a suitable environment.
Marriner (1907), who studied the habits of this species in New Zealand, states that it is strictly nocturnal, seldom emerging during the day. It is arboreal, often ascending several feet above the ground. Thorny bushes are easily negotiated.
According to Marriner (1907), who kept specimens under observation, this species spawns in the autumn, and eggs deposited on the 1st of March hatched out on the 11th and 12th of the same month. The tadpoles from these eggs did not mature, not even by the following autumn, but it seems likely that the artificial conditions under which the tadpoles were kept may have retarded their growth. It is doubtful whether under normal conditions the metamorphosis would have been so delayed.
Waite (1929), writing on the breeding of this species in Australia and Tasmania states: ‘The eggs are laid in water and are attached to submerged weeds in small bunches (fig. 188), which encircle the stems of the plants and may be found at almost any time of the year.’ My observations are confined to some specimens obtained for me by Capt. Ainsworth at Greymouth, West Coast, and on a small series of tadpoles collected by Mr. J. H. Sorensen at the mouth of the Waiau River, Southland, in January of 1939. Most of the specimens in this series were at the frog stage and would have left the water in about a week.
On November 7, 1959, I dissected a pair from the Greymouth set which I had kept alive. The female contained a large number of eggs, almost mature and deeply pigmented. The size of the ova suggested that they would have been voided within a fortnight or less. Compared with H. aurea the ova of H. ewingi are comparatively larger and considerably fewer in number, which in itself suggests a different breeding habitat to H. aurea.
If we may take the size of the ova in the Greymouth specimen and the estimated time of laying, November, and couple it with the tadpoles from the Waiau River area, January, it would appear that this frog completes its tadpole stage and metamorphosis in about two to three months time, that is, before the onset of winter.
A tadpole from the Waiaua set, with the hind limb buds just showing, measures 33 mm. in total length; another with the hind limbs fully developed 36 mm. (tail 22 mm.); a third with all limbs developed and the tail being absorbed, 33 mm. A young frog with the metamorphosis complete measures 14 mm. from snout to vent.
The lips of the tadpole are papillate (text-fig. I, fig. 2). There are two series of teeth above the beak, the upper continuous, but with a downward loop at the centre; the lower is formed of a series interrupted in the centre. Below the beak there are three continuous series. The upper portion of the beak is feebly denticulate; the lower markedly so. All teeth are shed at the time the mouth is assuming its final form.
Apparently the introduction of H. ewingi to New Zealand was an individual effort. A Mr. W. Perkins brought some frogs in a bottle from Tasmania in 1875, and liberated them in a drain in Alexander Street, Greymouth, South Island. They soon spread to the southern bank of the Grey River as far as Aharua and a few miles further southwards, but apparently did not succeed in crossing over to the north of the river. About 1900, Mr. James King introduced some of the Greymouth individuals into the Hokitika area where they survived and increased for a time, but as they are believed to be extinct in the area today, it is presumed that the larger and more voracious H. aurea was responsible for their extermination. H. ewingi is still prevalent in Westland.
H. ewingi is present in the Waiau River area (Southland) and is breeding. Recently Dr.
In 1946 Major R. Wilson attempted to introduce living individuals of H. ewingi from Westland into the North Island. This effort proved a failure. About two years later another attempt was made, this time using spawn from Barrytown. The experiment proved successful and the species has now spread northwards for about twenty miles from Himatangi, the original site of this liberation.
Pelodryas caeruleus (part) Guenther, 1858. Cat. Tailless Batr. Brit. Mus., p. 119, pl. ix, fig. B (Syst.).
Hyla caerulea Boulenger, 1882. Cat. Batr. Sal. s. Ecaud., 2nd Edit., p. 383 (Syst.); Fletcher, 1889. Proc. Linn. Soc. N.S.W., 2nd ser., 4: 381 (Breeding);
Gadow, 1901. Amphib. and Rept. Cambr. Nat. Hist. Ser., 8: 198, fig. 39 (Gen. Biol.); Thomson, New Zealand reference.
Tongue circular, free and very slightly notched behind. Vomerine teeth in two slightly oblique series on a level with the hinder edge of the choanae. Head broader than long; snout rounded, truncate; canthus rostralis distinct; loreal region slightly concave; interorbital space broader than the upper eyelid; tympanum very distinct, two-third the diameter of the eye. Fingers one-third webbed; no projecting rudiment of pollex; toes nearly entirely webbed; subarticular tubercles well developed; digital discs large, those of the fingers as large or somewhat larger than the tympanum, of toes a little smaller; a slight cutaneous fold along the inner side of the tarsus; tibio-tarsal articulation reaches hardly to the eye. Skin smooth, above, much thickened and studded with large pores on the back of the head and on the scapular region as far laterally as the strong curved fold bordering the eye; belly and lower surface of the thighs granulate. Male with an internal subgular vocal sac; during the breeding season brown rugosities appear on the inner side of the first finger. (After Boulenger, 1882.)
Males are smaller than females, the latter often exceeding slightly over 100 mm.
Male: (a) Snout to vent 68 mm.; hind leg 96 mm.; foot 42 mm.; longest toe 26 mm.; snout to nostril 4.5 mm.; snout to tympanum 19 mm.; snout to eye 10.5 mm.; eye 6 mm.; tympanum 4.5 mm.; distance between eyes (anterior corner) 13 mm.
(b) Snout to vent 83 mm.; hind leg 106 mm.; foot 51 mm.; longest toe 29 mm.; snout to nostril 5 mm.; snout to tympanum 21 mm.; snout to eye 13 mm.; eye 7 mm.; tympanum 4.5 mm.; distance between eyes (anterior corner) 18 mm. (Wanganui Mus.)
Upper surface a bright pea green, lower white, unspotted. (Colour from a fresh male specimen.) The upper surface of the male is similar to the female, but the flanks are spotted with white dots surrounded with dark haloes; armpits, groins and outer portions of thighs mushroom or mauve. Eye brassy.
Spread over the warmer parts of the Australian continent, but does not occur in the colder parts of Victoria nor in Tasmania. Specimens from the plains and drier regions are smaller than those which enjoy a more liberal supply of water.
Gadow (1901) gives a good account of the habits of this species. According to him, these frogs live well in captivity, and become confiding enough to take food from one's fingers. They are nocturnal, hiding by day and emerging at dusk. In hiding they simulate the colour of their surroundings; dark brown when resting in hollow logs or a tone of green to harmonise with the surface of the foliage they may be resting on. When at rest the limbs are tucked close under the body. In broad daylight the pupil, when at rest, is reduced to a tiny slit, but at night it enlarges to the full extent of the eye.
The food consists of earthworms, snails, insects and spiders. The food is generally lapped up by a flick of the tongue, but large or lengthy objects are ‘shovelled’ into the mouth by the aid of the forefeet in a ludicrous manner. The shells of snails are ejected through the mouth after their contents have been digested, much in the same way in which some birds of prey eject pellets of undigested parts of their prey.
Both sexes are said to have a voice, but that of the female is merely a grunting sound. The male is provided with internal vocal sacs. He inflates his throat and emits a sharp cracking sound, which can turn into a ‘regular bellowing like the gruff barking of an angry dog‘. They croak at any time of the year, particularly on the approach of showers of rain. Certain noises will induce them to bark. Once one has commenced others will join in the chorus.
In Australia breeding takes place in August and September, but abnormally dry conditions may result in the postponement of egg-laying to January. The eggs are laid in foamy masses which float on the surface of the water. The tadpoles pass their early development within the mass and enter the water from beneath.
Nothing is known of the breeding of this species in New Zealand, but I have seen a tadpole taken at Inglewood about June 26, 1952, and two from Puketaha, eight miles from Hamilton, on March 10, 1957. In both cases buds of the hind limbs were just visible.
A tadpole collected at Inglewood (text-fig. I, fig. 5) about June 26, 1952, with the hind limbs just appearing measures, in total length, 134 mm. (tail 89 mm. by 31 mm. at the deepest point, including membrane). Another two, taken at Puketaha on March 10, 1957, also had the hind limbs just appearing. The larger of the two specimens measures 112 mm. (tail 75 mm. by 28 mm. at the deepest point). These tadpoles give some
H. aurea or H. ewingi.
The lips are fringed with papillate processes. In the Inglewood specimen no horny teeth are visible above the beak, but this may be due to delayed or poor preservation. The imperfection of the series below the beak is probably due to the same cause (text-fig. I, fig. 3). In the Puketaha specimens two series are visible above the beak, the lower series being interrupted in the centre; below the beak there are three series (text-fig. I, fig. 4), the uppermost interrupted at the centre.
In 1897 the Agricultural Department received a consignment of six dozen of this species from Mr. J. Stein of Sydney. According to Mr.
The island of Motuihi in the Auckland area was also stocked with them. In the South Island, Mr. Kingsley liberated some on behalf of Dr.
There has been much speculation as to the survival of the species in the North Island. Mr.
Although no further adult specimens of H. caerulea have been obtained in the North Island, there is good reason to believe that the species still survives there, for on about June 26, 1952, a large tadpole was obtained at Inglewood and another two of about the same size at Puketaha on March 10, 1957. It is more than likely that this highly camouflaged, arboreal frog has so far escaped attention and still survives in suitable localities.
I wish to express my thanks to Dr.
On the high mountains of central New Guinea there are tropical montane forests, alpine tussock grasslands and herbfields which bear a remarkable physiognomic resemblance to similar communities in New Zealand and in which moreover, occur many species indicative of a yet closer affinity.
Many of these relationships stem from past tropical migrations southwards from Malaysia as for example the climbing Freycinetia and the terrestrial Elatostema. Of greater interest, however, are those plants which are apparently representative of a once more general distribution of a great southern flora which extended over Australia and reached out as far as South America.
These remnant plant distribution patterns evoke a stirring history of ancient plant migrations, of invasion and decimation under the influence of vast climatic fluctuations, of long-vanished land bridges and shifting continents. Was there once a warm and verdant Antarctica? Have islands and continents once close to each other, now drifted apart leaving deep intervening oceans? Were whole floras affected by the great ice ages? These are some of the problems of plant geography the solving of which depends upon data still being actively collected.
In this respect New Guinea with its large imperfectly known flora is emerging as an important refugium for much of the ancient southern flora which once covered the postulated southern continent of Gondwanaland. New and recent plant discoveries, particularly in the botanical exploration of the central mountains, are shifting the known generic centre of distribution in many instances. Even the typically subantarctic genus of Nothofagus is now represented by some sixteen species in New Guinea and a further five in New Caledonia. This contrasts with the two species remaining in Australia and the four to five in New Zealand. The New Guinea species produce pollen of the brassii type which is found only as Miocene fossils in New Zealand. Another example is the genus Carpodetus long quoted as monotypic to New Zealand, when in fact it has about six species in New Guinea. Recent collections in New Guinea's botanically unexplored mountains are adding new links with southern genera. This is particularly so in groups like the mosses. As late as 1942 E. B. Bartram wrote: ‘An interesting feature that does not seem to have been previously remarked is the close relationship of the alpine and
This does not necessarily signify that the centre of origin is in any way shifting to New Guinea but only that the high mountains of New Guinea may well represent a more important area for relicts of the ancient southern flora than New Zealand itself!
Large areas of New Guinea remain virtually unexplored in the botanical sense and with new species continually being added to the estimated total flora of some fifteen to twenty thousand species it is difficult to keep up to date with any taxonomic assessment. An ecological assessment of the vegetation is only in its initial phases.
One of the most comprehensive accounts of the mountain vegetation is to be found in Brass, 1941. This account deals with the results of the Third Archbold Expedition in 1938-39 to the Snow Mountains forming part of the Central Range in the Netherlands New Guinea. Of the eastern end of this Central Range, lying in Australian New Guinea, very little is known.
Until 1933 it was shown on maps as a rugged and uninhabited region. The Leahy brothers made the first penetration of the central highlands and their amazing discovery of a thriving stone-age population in these high mountain valleys still makes fascinating reading. It is well told in Colin Simpson's Adam in Plumes.
In 1956 Messrs. Hoogland and Pullen from C.S.I.R.O. carried out botanical collecting in the highlands area. This was in preparation for a full-scale land resources survey which was made during the following year. Some 4,000 square miles comprising the western and eastern highland district were surveyed in regard to soils, vegetation and geomorphology during a season lasting four months. The writer was plant ecologist with this team. Later (1958) Dr. R. D. Hoogland, taxonomist, published an account of the alpine flora of Mt. Wilhelm based on the collections made during the surveys and an account of the vegetation will be found in Robbins (in press). Mt. Wilhelm is the highest peak in eastern New Guinea and it is of interest to mention that Mr. L. J. Brass, botanist with the Archbold Expeditions, has recently returned from this area.
The Wahgi River valley, some seventy-five miles long and up to ten niles wide, constitutes the main highlands valley. The floor is some 5,000 eet above sea level and enclosed by two great mountain ranges running east-west. To the north is the Wahgi-Sepik Divide, part of the Bismarck Range system. Several high peaks are included along its length but lominating all is the massive granodiorite peak of Mt. Wilhelm rising to 5,000 feet and the highest point in Australian New Guinea.
The southern flanks are formed by the Kubor Ranges where many individual peaks attain heights of over 10,000 feet. Blocking the western end of the Wahgi valley is the volcanic Mt. Hagen.
The valley landscape is now one of open grassland throughout which are groves of Casuarina trees, clumps of feathery bamboos, native garden patches, tall cane grasses and remnant oak forest outliers. For perhaps hundreds of years the native inhabitants of the valley have progressively cleared back the forest in their quest for new garden land. Moving over the foothills to the very flanks of the ranges and along the small side valleys up to an altitude in some places of 7,000 to 8,000 feet, they have left behind them areas of short mixed grassland. Representing an entrenched
disclimax, these grasslands are perpetuated and extended by the practice of burning off the grasses periodically in search of small game. Grass species here are common to the extensive lowland grasslands of the adjacent Markham and Ramu valleys and with other plants associated with the domesticated parts of the highlands no doubt followed man in his migrations from the lowlands.
On dry sites Australian kangaroo grass (Themeda australis) dominates, otherwise a complex of Imperata (kunai grass), Arundinella, Sorghum nitidum, Ophiuros, and Capillipedium is found. Ischaemum barbatum covers moister depressions. Throughout these grasslands are a variety of associated herb species, mostly tropical weeds.
Regrowth, apart from the garden weeds springing up in abandoned plots, cannot be said to be a feature of the highlands. In the lower and drier eastern highlands around Goroka township the country is of rolling treeless grassland giving a pastoral aspect to the landscape. Further west in the Wahgi valley the Mt. Hagen volcanic ash is covered with a growth of tall canegrass, Miscanthus floridulus, and associated tree-fern and woody shrub regrowth. Here Dodonaea viscosa may be a common shrub together with
In making gardens, the natives start by felling the forest trees and burning the wood. Narrow lines of trenches are then dug in a squared pattern across the plot. The loose earth is heaped up on to these small squares and cuttings of the sweet potato vine, or ‘kau kau’, are planted. The highland natives are vegetarian apart from the odd pig-feasting days and sweet potatoes together with sugar-cane, bananas and, more recently, peanuts, corn, Irish potatoes and other European vegetables form the staple diet.
In garden areas many Casuarina tree seedlings are carefully planted and tended to later provide housing material, fuel and the split timber staves for the stout picket fences which enclose the gardens against the ubiquitous pigs raised for ceremonial feasting.
The natives have a flair for landscape gardening and line the roadways with useful and ornamental trees and shrubs. Features of the highlands are the park-like sing-sing or dancing grounds. These are bright with the variegated foliage of Acalypha, Cassia, Croton, Cordyline terminalis, Coleus, Salvia, Balsam and copper-leaved sugar cane. Forest tree seedlings such as Podocarpus and Papuacedrus are brought down from the mountains to plant in these sing-sing grounds. In the eastern districts the indigenous Eucalyptus deglupta and Araucaria cunninghamii are found as specimen trees in the villages.
The major interest of the New Zealand botanist, however, lies in the forested ranges. Almost invariably a climb of a thousand feet or more has to be made to pass the limits of cultivation and enter the forest edge at the 6,000 to 8,000 feet level. Usually the lower zone is dominated by several evergreen oaks bearing simple mesophyll leaves and large acorns. Castanopsis acuminatissima is the most frequent species while the others remain grouped under Quercus awaiting further taxonomic study. Above the oak zone, which is now largely cleared for gardens, the forest is either a Nothofagus beech forest or a mixed podocarp-broadleaf forest. Lower montane rain forest in New Guinea may begin at altitudes as low as 3,000 feet but there is wide variation in its composition throughout the island and the formation still requires much study. It is in such forest of the
Nertera
may catch the eye. Elatostema, Dawsonia, and familiar ferns may cover the forest floor while among the shrubs species of Piper, Pittosporum, Schefflera and Geniostoma are immediately identified. Even small trees belonging to Quintinia, Rapanea (Suttonia), and Winteraceae (Drimys and Bubbia) are unmistakable while in the canopy are Podocarpaceae, Elaeocarpaceae, Cunoniaceae, Lauraceae and Myrtaceae; all broadleaf families which dominate in New Zealand's mixed forests. The New Guinea montane forest, however, is far richer in genera and species the majority of which would be strange to a New Zealand botanist. The presence among these of such genera as Carpodetus, Litsea, Melicope, Olearia, Ascarina, Paratrophis and others give, as it were, but a New Zealand flavour to the vegetation. The gymnosperm element seldom reaches more than a stocking of eight to ten trees per acre although they constitute a valuable and sought-after softwood timber resource.
Podocarp species which are common in the lower montane forest are Podocarpus ledermannii, P. rumphii, P. imbricatus, P. amarus and P. neriifolius. The last three of these are the most frequent and seedling
P. amarus and P. neriifolius are both types with broad flat leaves and may be found occasionally in the lowland forests. Two species of Dacrydium also occur in the highlands. Dacrydium falciforme is a small tree resembling the New Zealand miro, while D. elatum is close to rimu in appearance. Both, however, are local to rare in the montane forests. Phyllocladus hypophyllus, and Papuacedrus (until recently Libocedrus sp.) belong more to the high montane forests.
The canopy of the lower montane forest is made up of a number of broadleaf species often reaching 100 feet or more in height. Genera such as Opocunonia, Schizomeria and Aistopetalum belonging to the Cunoniaceae are frequent. Elaeocarpaceae contribute many species of Elaeocarpus and Sloanea, while several Cryptocarya spp., a genus close to Beilschmiedia, represents the Lauraceae. Also here are Syzygium spp. (cf. Eugenia), and the lesser associates, Albizia, Astronia, Alphitonia, Elmerillia, Fagraea, Ficus, Guioa, Garcinia, Himantandra, Ilex, Planchonella, Pygeum, Perrottetia, Sterculia and Zanthoxylum.
In the second tree stratum with limits between 40-60 feet are to be found Elaeocarpus, Ackama, Weinmannia, Pullea and Gillbeea, all of the Cunoniaceae, Ficus and Syzygium spp., and a host of small trees such as Sphenostemon papuanum, Sloanea, Sericolea, Myristica, Daphniphyllum, Dillenia montana, D. schlechteri, Diospyros, Quintinia, Casearia pachyphylla, Litsea, Couthovia, Zanthoxylum, Discocalyx, Rapanea, Ardisia, Pittosporum pullifolium, Helicia microcarpa, Timonius, Evodia, Eurya, Gordonia papuana, Ternstroemia and the giant stinging tree, Laportea.
A dense shrubby layer includes the following: Olearia, Casearia angiense, Bubbia, Aglaia, Dichroa febrifuga, Rhododendron, Geniostoma, Mearnsia cordata, Decaspermum, and Xanthomyrtus.
Members of the Rubiaceae such as Amaracarpus, Psycotria, Mussaenda and Gardenia are very frequent while Melastomataceae is represented by Medinilla, Everettia and Poikilogyne. Small Pygeum spp., Eurya meizophylla and the ubiquitous Symplocos, also Pittosporum berberidoides, P. inopinatum, a new species discovered during the survey, Acronychia, Rhamnus, Evodia, Perottetia moluccana. Chloranthus and Ascarina are among the sub-shrubs.
Small palms, Pandanus spp., tree ferns such as Cyathea contaminans, Dicksonia and a tall Marattia as well as masses of climbing bamboo all contribute to the forest structure.
A rich ground flora includes Begonia, some Araceae, the forest sedges Carex, Scleria and Schoenus, the dwarf Pittosporum sinuatum, while several species of Pilea and Elatostema are particularly abundant. Alpinia is a common Zingiberaceae together with the two Rubiaceous herbs Ophiorrhiza and Argostemma. Piper species may be small shrubs or semi-climbers. On the floor and fallen logs are a Pratia sp., and Nertera granadensis, while Dianella is frequent. Among the many ground ferns are to be found species belonging to the genera Asplenium, Blechnum, Adiantum, Hymenophyllum, and Leptopteris. Here too is an abundance of lycopods and bryophytes.
Among the small climbers and scramblers present are Parsonsia, two species of Freycinetia, Rubus, Clematis, Smilax, Celastrus, Alyxia, Hoya and Secamone as well as members of the Gesneriaceae, Monimiaceae, and Bignoniaceae.
Epiphytes include Pittosporum ramiflorum, Schefflera, climbing ferns and orchids (including Dendrobium and Bulbophyllum) and parasitic Loranthaceae.
An excellent account of the discovery of extensive Nothofagus forests in New Guinea will be found in Van Steenis (1953). Some sixteen species are now recognised although the question of hybrids remains. With further recent collections, including those made by the C.S.I.R.O., a revision is already due.
Most of the New Guinea beeches are relatively large-leaved and with entire margins. However, on fruiting morphology van Steenis traces affinities with the New Zealand N. fusca group.
Beech forest has been recorded from about 3,000 feet to 10,000 feet in New Guinea but in the highlands its range was found to be between 7,500 feet to 9,000 feet. It descends, however, as a mixed element down to 4,500 feet in the eastern highlands. Nothofagus was not found to play any part in the formations above 9,000 feet and its true status appears to be as a member of the lower montane rain forest formations.
The New Guinea beech forest is a two-layered forest with a closed canopy of spreading and interlocking crowns which may consist of 75 per cent. Nothofagus species 90-100 feet high. It often forms a mosaic with the mixed broadleaf-podocarp forest occupying only one flank of the range or dominating on the ridges. In July the reddish flush of young leaves distinguished this pattern from some distance away while the distinctive crowns show up well on aerial photos flown at 25,000 feet. In the highlands the largest continuous areas of beech are to be found along the southern Kubor Range and it is virtually absent from the ranges flanking the northern periphery of the valley. The beech trees are seldom found as scattered individuals but even in mixed forest form small isolated gregarious stands. No doubt some interesting correlation with migration paths and environment as is evident in New Zealand will emerge when the full pattern of the New Guinea Nothofagus forest is mapped.
In these New Guinea mountains, beech forests exist side by side, as in New Zealand, with a mixed broadleaf-podocarp forest with usually a sharp boundary between the two. However, here one is in a montane forest of the tropics and the aspect is of a more luxurious and humid forest than in a subantarctic beech forest in New Zealand. There is less contrast with the adjoining mixed forest and indeed many of the subordinate species overlap. The fagaceous trees dominate and have a similar layered appearance and even-formed canopy as in New Zealand but mixed under-layers including Pandanus and climbing forest bamboo are present. The leaf litter is not heavy and topsoil, while tending to be acidic, is closely
Pandanus, present also in the mixed forest, impart a distinctive physiognomy to the beech forests of the New Guinea highlands.
Species to be found in the upper stratum include several Nothofagus species, Ackama, and other Cunoniaceae, Quintinia, and Podocarpus with oaks, Cryptocarya, Zanthoxylum and Alphitonia.
The second stratum at about 30 to 50 feet may be sparse although rich in species. The smaller trees here include Nothofagus, Weinmannia and Pullea. Also several Ficus species, the Rubiaceous Timonius and Psychotria, two species of Drimys, Rapanea and other Myrsinaceae, Syzygium spp., Evodia (cf. Melicope) and Couthovia, a Schefflera, and Sloanea (Elaeocarpaceae).
Common members of the shrub layer are Symplocos, Sphenostemon papuanum, Polyosma, Medinilla, Piper, Pittosporum pullifolium, Helicia microcarpa.
Epiphytes are quite frequent, consisting mainly of pteridophytes, a small Freycinetia, orchids and scrambling Gesneriaceae.
The ground layers include ferns such as Blechnum and Hymenophyllum, with Pilea and Elatostema, terrestrial orchids, lycopods and bryophytes.
At 9,000 feet above sea level there is a change, often quite abrupt, in the forest formation. Above this level in the highlands are the regions of prolonged daily cloud cover and the so-called ‘mossy’ forest commences.
A single tree-layered community, montane cloud forest is dominated by species of Myrtaceae and Podocarpaceae. The canopy is compact and low, being 35-40 feet high, and made up of close slender trees often crooked in growth. The branches and indeed the whole forest floor are typically festooned and carpeted with masses of bryophytes, both mosses and liverworts.
The bamboo and screwpines of the lower montane zone forest are now absent altogether and filmy ferns and tree ferns find true expression. All tropical features have gone and the atmosphere is damp and dripping. The leaves are smaller, coriaceous and dark green, giving a drab appearance to the forest.
Myrtaceae are well represented by species of Decaspermum, Xanthomyrtus, Eugenia and Syzygium. Also Schefflera, Daphniphyllum, Quintinia, Elaeocarpus azaleifolius, Rapanea, Carpodetus, Drimys, Schuurmansia, Eurya, Pygeum, and Rutaceae.
The mountain podocarps include Podocarpus compactus, P. brassii and P. pilgeri. Papuacedrus and Phyllocladus are also frequent.
A sparse shrub layer may include Polyosma, Rhododendron spp., Vaccinium spp., Amaracarpus, Symplocos, Pittosporum spp., Piper and, appearing here for the first time, a low Coprosma.
Orchids, ferns and bryophytes make up the ground layer which, in more open glades may include Acaena anserinifolia, Libertia pulchella, Uncinia sp., Elatostema and Pterostylis.
At altitudes of 11,000 feet the upper limits of the cloud forest are fringed with a dense, low, woody vegetation or alpine shrubbery, patches of which may extend out into the alpine grassland.
The closed shrub layer, 15-20 feet high, consists of many Rhododendron and Vaccinium species together with Acronychia, Olearia, Saurauia, Schefflera, Sericolea, Symplocos, Pygeum, Decaspermum, Rapanea, Quintinea, Coprosma, Pyschotria, and Amaracarpus, Pittosporum, Polyosma, Eurya and Drimys.
These levels are above the prolonged mists of the cloud forest and emergent Podocarpus and Libocedrus may occur but there is little development of the high mountain forest formation described by Brass around Lake Habbema in Dutch New Guinea and also reported for the Owen Stanley Range.
Mosses and liverworts are abundant in the alpine shrubbery. Epiphytes include Loranthaceae, Orchidaceae and Pteridophyta while as a ground cover are Polystichum, Belvisia, Blechnum and the herbs Trigonotis, Libertia pulchella, Cardamine altigena, Acaena anserinifolia, Triplostegia glandulifera, Oxalis magellanica, Rubus moluccanus, Lycopodium, Galium, Epilobium and Geranium.
Above the tree-line at 11,000 to 12,000 feet the vegetation becomes tussock grassland. Extensive alpine grasslands occur on the summit areas of Mt. Giluwe, Mt. Hagen and Mt. Wilhelm and make an appearance on some of the higher isolated peaks of the two ranges. Here a New Zealand botanist is quite at home. Large tussocks of Hierochloe longifolia and Deschampsia Klossii dominate, forming clumps 2-3 feet high. In between grow the smaller tuft grasses represented by Danthonia archboldii, D. vestita, D. schneideri, and D. semiannularis.
Other grasses recorded are Deyeuxia, Agrostis, Anthoxanthum, Festuca papuana and the minute Poa crassicaulis and P. callosa.
Alpine herbs, many of which form cushion plants, grow among the tussocks in a mat of mosses and lichens. Here may be found Centrolepis phillippinensis, Hydrocotyle sibthorpioides, Oreomyrrhis papuana (syn.
Ferns include Gleichenia, the endemic Papuapteris linearis with Schizaea fistulosa as a new record. Lycopodium scariosum and the sedges
On higher slopes the soil is drier and more shallow with rocky outcrops. The tussocks thin out and small woody shrubs include Styphelia, Gaultheria mundula, Drimys brassii, Detzneria tubata, Kelleria (syn. Drapetes) papuana, Coprosma, Eurya brassii var. erecta, Hypericum macgregorii, Hebe albiflora and H. celiata. The last-mentioned are not whipcord hebes but similar to the New Zealand H. catarractae.
At the highest point on Mt. Wilhelm, 14,950 feet above sea level, plants still form a sparse rock crevice community between the moss-covered granodiorite rocks. Here the mountain mosses Andreaea rupestris and Rhacomitrium lanuginosum var. pruinosum, which occur together with Rhacomitrium crispulum, were collected for the first time in New Guinea. All are common New Zealand alpine mosses. The plants recorded here are the grasses Danthonia vestita, Poa callosa, Festuca papuana, Deyeuxia, Agrostis; the ferns Papuapteris linearis, Gleichenia bolanica and the small herbs, Cerastium keysseri, Lactuca, Ischnea elachoglossa and Trigonotis papuana. While again there are sufficient New Zealand genera and even species to strongly ‘flavour’ the vegetation an anlysis of the Compositae and the Ericaceae, for example, shows a marked difference, and reduces the apparent affinity.
The vegetation of montane New Guinea is only just becoming known. Already some confusion in the available literature reflects the great variation in local sites throughout this great island - hence the present account must be taken as referring essentially to the central highlands in Australian New Guinea.
The fascination of these montane forests lies in their affording a key to past southern floras. Thus the mixed lower montane forests of the highlands may be regarded as tropical outliers, now relict, of New Zealand's podocarp-broadleaf forests of tawa-hinau-kamahi and scattered rimu-totara-matai and miro.
In addition it contains many genera and species lost in New Zealand during the general post-Miocene regression as, for example, the warmthloving Nothofagus brassii group.
In the central highlands the major plant formations encountered are:
In my article entitled ‘An Empirical Method of Describing Stands of Vegetation’ (Tuatara, Vol. VIII, No. 1) there is a slip in identification: for ‘Pittos. kirk’ in Fig. 3 read ‘Pittos. corn‘.
One or two people have taken exception to the example of inflexibility in the study of vegetation I gave in the article, namely the Braun-Blanquet school of phytosociology, so I offer a few words of explanation. It is the school of course that is inflexible, not Braun-Blanquet. A school is a group of ‘disciples or imitators or followers’ and by definition implies rigidity in thought and practice. Many other examples of inflexibility in scientific study could have been given, including several indigenous ones from New Zealand (I would be inviting further reaction if I named them!). In my opinion the cause of science will be better served by individual contributions than by the growth of schools. September, 1960
We would like to point out that not everyone agrees with the opinion expressed by Tuatara 8, 1959, p. 1) about the Braun-Blanquet school of phytosociology. J. Major, who trained in Zurich in 1950, reviewed in Ecology (40, 1959, pp. 330-331) two recent papers by Braun-Blanquet and collaborators. He refers to the now classic study of Braun-Blanquet and Jenny (1926) on ‘Vegetation development and soil formation in the alpine belt of the central Alps’, and of the most recent monograph states ‘the conclusions are grouped around the parallelism of vegetation development and soil formation and a basic inventory of plant communities and soils forms the basis of the dynamic point of view which permeates the whole work‘. Everyone who has had the privilege of seeing Braun-Blanquet
Plant Sociology, translated by Fuller and Conard, 1932, pp. 26-27.)
In the article by Tuatara (Vol. VIII, No. 2, May 1960), page 66, Legend to Figures, for Fig. 2: (a) read Fig. 2: (b); and for Fig. 2: (b) read Fig. 2: (a).
Dr. Tuatara. We are grateful for the contribution he made towards establishing this journal, and in extending our good wishes to him and his family in Washington, may we express the hope that Tuatara will in due course once again come under his able editorship.—