Botanical Discovery in New Zealand: The Resident Botanists
Thomas Frederic Cheeseman (1845–1923)
Thomas Frederic Cheeseman (1845–1923)
For more than twenty-five years Colenso was the only resident New Zealand botanist seriously trying to uncover the secrets which the native flora had held for so long. Then two other men living in this country began to collect extensively and to publish papers describing their findings. One was Thomas Kirk and the other Thomas Cheeseman. Kirk's first paper preceded Cheeseman's by three years.
Cheeseman was born in Hull, Yorkshire, in 1845 and came out to New Zealand with his parents in 1853, the year in which Hooker published the first part of his Flora Novae Zelandiae. Curiously enough, the ship that brought out the Cheeseman family was named the Artemisia, the name the great Swedish botanist Linnaeus gave to a genus of plants belonging to the daisy family.
T. F. Cheeseman
In 1874, when he was nearly thirty years old, he was appointed secretary of the Auckland Institute and curator of the Museum, and from that time onwards was able to devote his whole time to scientific work. He had already published some papers on botanical subjects, and now he decided to specialize in botany. There being no room in the Museum, he kept the collection of plants he had begun to make in his own home, and there he built it up over the next fifty years. He had other interests (a Museum curator is always interested in more than one subject) and so, as the years went by, he published papers on mollusca, birds, reptiles, bats, fishes, and the Maori. But his main interest was always plants.page 13
Among the first studies that Cheeseman made on the plants of New Zealand was one on cross-pollination in native orchids and other plants. He made a special study of the devices which ensured that pollen should not be deposited on the stigma of the same flower but should be transferred by insects or birds to other flowers, either on the same or on other plants.* Charles Darwin had already shown, by a series of experiments, that the seeds of cross pollinated plants produce more vigorous and more healthy seedlings than do those of self-pollinated plants. Cheeseman first studied one of the small hooded orchids (Pterostylis trullifolia). In the flower of this orchid there is an upright column in the centre, bearing the stigma, and above this two pollen masses between side wings. One of the petals, called the lip, is in a horizontal position in front and has a little sensitive trigger-like projection at its base. When an insect alights on the lip and touches the trigger, the lip springs up and the insect is caught between it and the column. To get out of the flower it must crawl up the column and in doing so must touch the stigma, where it deposits any pollen it may have brought from another flower. Then, on crawling further up the column, it touches the pollen masses and is sure to drag off some pollen, which probably sticks to the stigma of the next flower visited. And so the peculiar structure of this orchid, as indeed of most orchids and of many other kinds of plants, is designed to ensure cross-fertilization. Cheeseman sent his description of the flower of Pterostylis to Charles Darwin, who included it in his book on the Fertilization of Orchids.
* The transfer of pollen from one flower to another is called cross-pollination and results in cross-fertilization. When the pollen falls on the stigma of the same flower it is referred to as self-pollination or self-fertilization.
Cheeseman carried out his first botanical explorations near home, on the Waitakerei Ranges near Auckland, where he collected altogether four hundred and sixty kinds of flowering plants, pines, and ferns. Among notable species he gathered were the manoao (Dacrydium kirkii)—a tree related to the rimu but having its young leaves more than an inch long and its old leaves only an eighth of an inch long—and the tropical umbrella fern (Stitcherus fiabellata). Cheeseman published the results of his work in 1872, giving a list of the species and descriptions of the plant formations (those of the forest, scrub, swamp, and so on). He has an interesting note on the scrub area on the eastern foothills, which are occupied mainly by manuka and bracken. Cheeseman says that the barren appearance of this part of the district is due mainly to the practice of burning off the vegetation every summer. We are now, after a further eighty years of European occupation, well aware of the destructive effects of such methods of trying to get grass to grow quickly.
Cheeseman next went further afield, and twice, in 1877 and in 1879, climbed to the crater ridge on the eastern side of Pirongia mountain. The vegetation on the summit ridge was so dense that in some places ‘The only means of advance was by walking on the tops of the trees themselves, the branches being so closely interlaced and matted together as to bear the weight of a man for con page 15 siderable distances. This mode of progression is not without its disadvantages, as on reaching a weak place the explorer usually descends to terra firma much more suddenly than is at all pleasant or convenient.’ He could not penetrate to the western side because of the close rough vegetation and, on his second visit, because some Maoris objected to his being there.
In August 1887 Cheeseman was able to visit the Kermadec Islands to collect plants, as the New Zealand Government despatched the Stella there for purpose of annexing the group to the colony of New Zealand. Cheeseman landed on Raoul Island every day for a week,* and with a large bag over each shoulder traversed as much of the island as he could, filling his bags with specimens. Raoul Island is mainly covered with forest, the principal tree being the Kermadec pohutukawa (Metrosideros kermadecensis). This species resembles the New Zealand pohutukawa but has shorter rounder leaves and bears flowers all the year round. The other kinds of trees are partly the same as those found in New Zealand, for example, karaka, ngaio, mahoe, koheriki, and parapara, and partly species not found anywhere else. Among these is the Kermadec nikau palm, a larger species than the New Zealand nikau, with round instead of oblong fruit. On his return to New Zealand Cheeseman sent specimens of this palm to the Italian botanist Beccari, who had made a special study of palms. Beccari said it did not belong to any described species so he published a description of it, naming it Rhopalostylis cheesemanii.
A few stone adzes of Polynesian type have been found on Raoul Island so it was not surprising that Cheeseman found two kinds of trees which evidently were brought from the Pacific Islands, perhaps by the Maoris on their migration to New Zealand. These were the candlenut and the ti (Cordyline terminalis), both plants furnishing products useful to the natives of the Pacific Islands. The candlenut provides candlenut oil and the root of the ti a sweetish starchy food, from which also an intoxicating drink can be fermented.
Cheeseman was thus the first botanist to collect plants on the Three Kings Islands.
In December 1895 Cheeseman, with Mr J. Adams, went to Mangonui by steamer and from there began walking towards the far north.They took a pack horse to carry their gear, food, and collecting-material. Following the shore of Doubtless Bay they found some notable New Zealand plants. There was the tawapou (Planchonella costata), a beautiful and now very rare tree with shining green leaves and polished seeds that were formerly used by the Maoris for making necklaces. At Cooper's Beach they saw the southern royal fern (Todea barbara), rare in New Zealand. This belongs to the same family as the royal fern (Osmunda regalis), widely distributed in the northern hemisphere. There was plenty of the New Zealand dodder (Cassytha paniculata), a twining leafless parasite infesting mostly the manuka, which it sometimes almost smothers. They then crossed the island to Ahipara on the west coast, where Cheeseman found the beautiful Hibiscus diversifolius. Here, too, they saw two plants of the Polynesian ti (Cordyline terminalis), one of the food plants introduced by the Maoris before the Europeans came to New Zealand and one still widely cultivated in the Pacific. From Ahipara Cheeseman and his companion walked along the Ninety Mile Beach, where they found the pretty trailing Fuchsia procumbens, the only species of Fuchsia that has upright flowers. On the way from Parenga to Cape Maria van Diemen the travellers passed the great pohutu- page 17 kawa tree which the Maoris call Kahika. It was almost covered in sand but was quite healthy, and was used as one of the leading beacons for vessels entering Parengarenga harbour.They saw, too, the beautiful, deep purple flowered koromiko (Hebe speciosa) in this district. This species is now widely cultivated in public and roadside gardens. Cheeseman and Adams continued their journey to the North Cape and back to Parenga, from where they took the steamer Staff a to Auckland.
Cheeseman visited many other parts of New Zealand collecting plants for his herbarium. He investigated the central mountains of the North Island, Tongariro and Ruapehu, the Mount Arthur district in Nelson, and the Mount Cook district in Canterbury. From all these places he brought back the specimens which were afterwards to be so useful when he was writing his Manual of the New Zealand Flora.
In the winter of 1899 Cheeseman visited Rarotonga in the Cook Island group. He travelled all over the island, climbing the mountains, and on his return to New Zealand published a full account of the plants in the Transactions of the Linnaean Society of London. He also wrote a paper on Polynesian food plants, in which he had become interested.
Cheeseman's books on the plants of New Zealand comprise two editions of the Manual of the New Zealand Flora and two large volumes entitled Illustrations of the New Zealand Flora. Hooker's Handbook of the New Zealand Flora had appeared in 1864, but botanical exploration had gone steadily on, especially through the efforts of Colenso, Cheeseman, Kirk, and Petrie. So the demand for a new flora increased as the years went by and, about 1890, the Government commissioned Thomas Kirk to prepare the manuscript for one. Kirk worked on the book for several years but unfortunately died before it was completed. His manuscript, covering about half the flora, was published under the title The Students’ Flora of New Zealand. The Government then invited Cheeseman to undertake the work. Cheeseman accepted this offer and was given two days leave from the Museum each week for research and writing. His book appeared in 1906 under the title Manual of the New Zealand Flora. It contained descriptions of 1,551 flowering plants, 20 pines, and 156 ferns and fern allies. The completion of the Manual after about four and a half years' work was a great achievement for Cheeseman, and an event in New Zealand botany; but more was soon to follow. In 1914 the Illustrations was published. It contained two hundred and fifty fine drawings of New Zealand plants by Miss Matilda Smith page 18 of the Kew Herbarium. She worked from the specimens Cheeseman sent to England, many of them preserved in spirit so that Miss Smith would have the flowers in as natural a state as possible. Along with each plate was a page or more describing the plant, written by Cheeseman. The Manual sold out in about fifteen years, and Cheeseman began work on a new and enlarged edition. He was, however, not to see the finished work, as he died just after completing the manuscript. The book was published in 1925 with the introductory chapters brought up to date by the author of this Bulletin.
Cheeseman's collection of dried plant specimens was kept in his own house in cabinets made of specially selected kauri timber, with every specimen properly classified, mounted, and labelled. Except for a few doubtful kinds, his collection contains specimens of all the species he describes in the Manual. After Cheeseman's death the herbarium, including the cabinets, was transferred to the Auckland Museum. The great value of the collection lies in its type specimens, that is, those which he used when he was describing his new species; the rest of the collection contains specimens illustrating his views on the limits of the species as defined in his books.
Cheeseman's scientific achievements were recognized by his election to the Presidency of the New Zealand Institute, by the award by the same society of the Hector Memorial medal for botany, and, just before his death, by the award of the gold medal of the Linnaean Society of London. This is one of the highest honours given for botanical work and Cheeseman is the only New Zealander who has received the medal.
Cheeseman's name is commemorated in the genus Cheesemania, which belongs to the cress family. It contains five species found in isolated mountain districts of New Zealand and is nowhere common. The name cheesemanii is borne by twelve species of New Zealand plants. Among them are the Kermadec Islands nikau (Rhopalostylis cheesemanii), the common pondweed (Potamogeton cheesemanii), a forget-me-not (Myosotis cheesemanii), and a filmy fern (Hymenophyllum cheesemanii).
Redrawn by Richard Sharell,
after Miss Matilda Smith
Cheeseman's influence on botanical research in New Zealand was far-reaching. All his fellow-botanists here, at one time or another, sought his decision on some question of plant classification. He provided a carefully drawn up description of every known species of New Zealand flowering plant, pine, and fern, and thus gave the necessary basis for future research. His was indeed a great contribution to the study of the flora of New Zealand.