Tuatara: Volume 3, Issue 1, May 1950
The Classification of New Zealand Hepaticae
The Hepaticae or liverworts form the second of the two classes into which the Bryophyta are divided. The two main distinctions between the classes are said to be, that of the liverworts have unicellular rhizoids, and spiral elaters mixed with the spores in the capsules (except in Ricciaceae). The non-thalloid or foliose hepatics differ from the mosses, generally speaking, in the following respects; in the rudimentary and short-lived protonema; in the bi-lateral leaves always without a midrib, and frequently bilobed; in the usual presence of stipules; in the capsule remaining in the more or less delicate calyptra (destitute of lid) till the spores are mature, then developing a hyaline and evanescent, sometimes elongated seta, and commonly dehiscing by four valves, peristome always absent. Generally speaking, the liverworts prefer wetter conditions than the mosses.
Probably the earliest collection of New Zealand hepatics was that of Archibald Menzies, gathered at Dusky Sound in 1791. These were described and figured by Sir William Hooker in his Musci Exotici in 1818. Sir Joseph Hooker's Botany of the Antarctic Voyage, in several volumes spread over many years, contains the descriptions of plants collected by Hooker in the subantarctic islands, Northland (N.Z.), and Tasmania, together with many of Colenso's. Dr. T. Taylor and W. Mitten were responsible for these descriptions. In 1867, Part II of Hooker's Handbook of the New Zealand Flora was published, a portion of which is devoted to the liverworts, with an Appendix by Mitten. Dealing with plants collected by the earlier botanists, the Handbook has been the basis of all our work on New Zealand Hepaticae. Stephani's famous Species Hepaticarum in 6 volumes, 1900-1924, includes descriptions of all New Zealand species to date. Local Floras of both hemispheres are useful for obtaining information about hepatics, the handiest, perhaps, being L. Rodway's “Tasmanian Bryophyta II, Hepatics.”*
The system of classification used in this paper, is that set out by Evans.**
Three of the four orders of the Hepaticae are represented in New Zealand.
* Papers & Proc. Roy. Soc. Tasmania 1916.
** Evans, A. W., 1939. Classification of the Hepaticae, Botanical Review, vol. 5, p. 20.
Order 1 Jungermanniales
Plants both foliose and thalloid, the latter not differentiated into layers of different tissue and without pores. Tuberculate rhizoids not present. Sexual organs usually in groups, but not on special pedunculate receptacles. Capsule, usually on a long seta, opening by 4 valves. Apical growth of stem or thallus proceeds from a single cell.
Sub-order 1 Haplomitrineae
- Family Haplomitriaceae, Calobryum.
Sub-order 2 Jungermannineae (Jungermanniales acrogynae)
- Family Ptilidiaceae, Herberta, Mastigophora, Hygrobiella, Ptilidium, Bleoharostoma, Isotachis, Lepicolea, Lepidolaena, Trichocolea.
- Family Lepidoziaceae, Bazzania. Acromastigum, Psiloclada, Lepidozia.
- Family Cephaloziaceae, Cephalozia, Lembidium, Zoopsis, Adelanthus, Marsupidium.
- Family Cephaloziellaceae, Cephaloziella.
- Family Harpanthaceae, Lophocolea, Chiloscyphus, Mylia, Geocalyx, Saccogyna.
- Family Jungermanniaceae, Lophozia, Sphenolobus, Anastrophyllum, Cuspidatula, Chandonathus, Jungermannia, Jamesoniella, Acrobolbus, Symphyomitra.
- Family Marsupellaceae, Gymnomitrium.
- Family Plagiochilaceae, Plagiochila, Tylimanthus.
- Family Scapaniaceae, Diplophyllum.
- Family Schistochilaceae, Schistochila, Balantiopsis.
- Family Porellaceae, Porella.
- Family Goebeliellaceae, Goebeliella.
- Family Radulaceae, Radula.
- Family Frullaniceae, Frullania.
- Family Lejeuneaceae, 18 genera, originally subgenera of Lejeunea, keyed separately.
Sub-order 3 Metzgerineae (Jungermanniales anacrogynae)
- Family Treubiaceae, Treubia.
- Family Fossombroniaceae, Fossombronia Petalophyllum.
- Family Pelliaceae, Calycularia, Allisonia.
- Family Pallavicineaceae, Pallavicinia, Symphyogyna, Hymenophytum.
- Family Metzgericeae, Metzgeria.
- Family Riccardiaceae, Riccardia.
- Family Monocleaceae, Monoclea.
Order 2 Marchantiales
Thalloid, vegetative body consisting of epidermis, an upper zone of green tissue with or without air-chamber (with pores) and a lower page 22 zone of large-celled hyaline tissue. Rhizoids smooth and tuberculate, ventral scales or ridges often present. Special cells with oil-bodies present.
- Family Marchantiaceae, Marchantia, Lunularia.
- Family Rebouliaceae, Reboulia, Asterella, Plagiochasma.
- Family Targioniaceae, Targionia.
- Family Ricciaceae, Ricciocarpus, Riccia.
Order 3 Anthocerotales
Thalloid, with smooth rhizoids, no ventral scales. Cells usually with one large chloroplast. Sporogonium with a bulbous foot, a sheath, and a long sessile capsule, bursting from the top downwards into two valves, columella generally present. Antheridia sunk in the upper surface of the thallus, ultimately bursting free.
Family Anthocerotaceae, Anthoceros, Aspiromitus (on the authority of Pearson), Megaceros, Dendroceros.
Key to Genera
|2.||Leaves (plus or minus) reduced to cauline lobes, cells inflated||Zoopsis|
|Leaves not reduced to cauline lobes||3|
|3||Leaves spirally arranged||Calobryum|
|Leaves not spirally arranged||4|
|4.||Archegonia on the upper surface of a thalloid stem (Fig. 30, P)||Fossombronia|
|Archegonia at first terminal on stem or branch, involucre formed from true leaves||5|
|5.||Elaters with one spiral band, capsule valves not split to the base||6|
|Elaters with 2 or more spiral bands, capsule valves split to the base||7|
|6.||Branches intra-axillary, lobule convex towards the upper lobe (Fig. 13, B)||Frullania|
|Branches infra-axillary, lobule concave towards the upper lobe||Lejeuneaceae|
|7.||Leaves incubous or transverse||8|
|Leaves succubous to transverse||19|
|8.||Leaves with an upper (dorsal) lobe and lower (ventral) lobule||9|
|Leaves without a ventral lobule||12|
|9.||Dorsal lobe and ventral lobule closely complicate||10|
|Lobe and lobule not closely complicate||11|
|Stipules absent (Figs. 9, 13 C)||Radula|
|11.||Dorsal lobe with 2 diverging lobules (Fig. 12)||Goebeliella|
|Ventral lobule and segments of stipules often saccate||Lepidolaena page 23|
|12.||Leaf margins lobed, sometimes toothed, stipules large, resembling leaves||Isotachis|
|Leaves transverse, concave-complicate, shortly bi-lobed||13|
|Leaves incubous with long tapering lobes||14|
|Leaves shaped otherwise||15|
|13.||Leaves imbricate, sometimes papillose, perianth ventral, basal||Lembidium (excluding two dendroid species)|
|Plants weak, hyaline, perianth terminal||Hygrobiella|
|14.||Leaves bi-lobed, homomallous||Herberta|
|Leaves twice bi-lobed or 3-5-lobed, dorsal margin sometimes dentate-ciliate||Lepicolea|
|15.||Leaves unevenly 2-lobed, plant pendulous, flagelliferous||Mastigophora|
|Leaves 3-6 deeply cleft||16|
|Leaves usually flat, longer than mid-width, apex 2-3-toothed||18|
|16.||Perianth scaly, leaves with numerous hair-like divisions||Trichocolea|
|17.||Branches sometimes attenuated, leaf-segments usually entire, sometimes toothed (Fig. 8)||Lepidozia|
|Branches not attenuated, leaf-segments fringed with long cilia||Ptilidium|
|18.||Leaf-apex usually 3-toothed, ventral branches from the axils of the stipules (Figs. 4, 5)||Bazzania|
|Leaf-apex 2-dentate or 2-lobed (entire in an undescribed species), ventral branches from the side of the stipules||Acromastigum|
|19.||Leaves with a smaller dorsal lobe (equal in Diplophyllum densifolium)||20|
|Leaves without a dorsal lobe||22|
|20.||Stipules absent (Fig. 2)||Diplophyllum|
|21.||Dorsal lobe usually broader than tall, sporophyte in a terminal fleshy cup||Schistochila|
|Dorsal lobe usually taller than, or as tall as broad, sporophyte terminal in a marsupium (Fig. 6)||Balantiopsis|
|22.||Cauline stipules present||23|
|Cauline stipules absent (except in Jungermannia rotata)||29|
|23.||Leaves 3-6 deeply cleft||24|
|Leaves shaped otherwise||25|
|24.||Leaf-segments spiny, in one plane, perianth terminal||Blepharostoma|
|Leaf-segments erect from a spreading base, perianth lateral||Psiloclada|
|25.||Perianth terminal on main stem (rarely lateral in Lophocolea)||26|
|Perianth or marsupium lateral (rarely terminal in Chiloscyphus)||27page 24|
|26.||Perianth 3-gonous, third angle dorsal (Fig. 10)||Lophocolea|
|Perianth laterally compressed, mouth 2-lipped||Mylia|
|Perianth deeply multiplicate, leaves undulate, bilobed, plants robust||Chandonanthus|
|27.||Sporophyte in a campanulate perianth (Fig. 7)||Chiloscyphus|
|Sporophyte in a fleshy marsupium||28|
|28.||Leaves and stipules deeply bifid||Geocalyx|
|Leaf-apices entire or irregularly sub-entire, papillose||Saccogyna|
|29.||Sporophyte not in a marsupium, usually a perianth||30|
|Sporophyte in a marsupium||40|
|30.||Perianth terminal on main stem or branches||31|
|Perianth remote from apex (sometimes terminal in Cephalozia), branches ventral||39|
|31.||Perianth laterally compressed, leaves usually toothed (Fig. 30, O)||Plagiochila|
|Perianth shaped otherwise or absent (in Gymnomitrium)||32|
|33.||Plants robust, reddish||Anastrophyllum|
|Plants minute to small||34|
|34.||Perianth absent, leaves closely imbricate, complicate, only shortly bilobed||Gymnomitrium|
|Leaves sub-remote to remote||35|
Legends to Figures
1. Diplasiolejeunea lyratifolia ventral, showing duplicated stipules, one for each leaf, × 10.
2. Diplcphyllum domesticum dorsal, showing small dorsal leaf-lobes, × 5.
3. Strepsilejeunea Curnowii ventral, showing acute, decurved leaf-apices, × 10.
4. Bazzania Novae-Zelandiae ventral, showing incubous leaves and ventral axillary branching, × 4.
5. Bazzania Novae-Zelandiae dorsal, showing incubous leaves, × 4.
6. Balantiopsis diplophyllum dorsal, showing terminal marsupium, × 6.
7. Chiloscyphus ammophilus dorsal, showing succubous leaves, × 5.
8. Lepidozia tetradactyla dorsal, showing deeply divided leaves and lateral perianth, × 8.
9. Radula Levieri ventral, showing lobules, absence of stipules and spent capsule, × 10.
10. Lophocolea subporosa dorsal, showing terminal perinath with 3rd keel dorsal, × 5.
11. Cephaloziela sp., dorsal, showing deeply pluri-plicate perianth and bi-fid leaves, × 12.
12. Goebeliella cornigera ventral, showing double lobules and entire stiples, × 10
13. Elaters, A Metzgeria violacea monospiral, × 125; B. Frullania rostallata monospiral; C. Radula Levieri bispiral.
14. Pseudolates of Anthoceros × 100.
15. Cells of Lejeunea sp. without trigones, ca. 40 microns.
16. Rhizoids; D. Reboulia hemispherica, smooth; E. Lunularia cruciata, tuberculate, × 125.
|35.||Perianth pluriplicate, branches ventral (Fig. 11)||Cephaloziella|
|Perianth ovate, mouth plicate, branches lateral||36|
|Leaves (more or less) concave||Lophozia|
|37.||Leaf-apex acute or cuspidate||Cuspidatula|
|38.||Medium to robust, leaves erect, imbricate, invol. stipule present||Jumesoniella|
|Small to medium, leaves soft and crumpled, invol. stipule usually absent||Jungermannia|
|39.||Plants small, perianth trigonous, third angle ventral, leaves two or more lobed||Cephalozia|
|Plants medium to sub-robust, perianth cylindrical, leaves not lobed||Adelanthus|
|41.||Stems erect, marsupium pendulous, hairy||Tylimanthus|
|Stems prostrate, marsupium smooth||42|
|43.||Sporophyte sunk in the tissues of the thallus||44|
|Sporophyte not sunk in the tissue of the thallus||45|
|44.||Epidermis without pores, antheridia scattered||Riccia|
|Epidermis without pores, antheridia in a median furrow||Ricciocarpus|
|45.||Sporophyte an erect linear organ of two valves dehiscing downwards||46|
|Archegonia in other combinations from the thallus||49|
17. Asterella australis × 16, F carpocephalum showing laciniate perianth, × 4.
18. Targionia hypophylla with terminal valves, × 1½.
19. Riccardia marginata showing absence of nerve and lateral calyptra, × 3.
20. Anthocercs with linear dehiscing capsule, nat. size.
21. Marchantia with male carpocephalum and rounded gammae cups; G. female carpocephalum showing involucres between the rays, nat. size.
22. Metzgeria furcata dorsal with ventral calyptras showing, also mid-rib and ciliate margins; H. ventral with male branches, x. 4.
23. Reboulia hemisphaerica, carpocephalum, underneath view showing bi-valved involucres, × 2½.
24. Plagiochosma australe with invol. lobes opening vertically, × 2½.
26. Lunularia cruciata with lunate gemmae cups, nat. size.
27. Sypmhyogyna hymenophyllum showing involucral scales and calyptras; I. sterile archegonia adhering to calyptra, × 2.
28. Pallavicinia Lyellii, J. invol. cup, K. perianth with calyptra included, nat. size.
29. Hymenophytum phyllanthus, L. basal ventral invol. cup, M. perianth, calyptra included, nat. size.
30. Dehisecnt capsules; N. Taxilejeunea Colensoana showing valves not divided to the base, × 10; O. Plagiochila × 7; P. Fossombronia × 7; Q. Metzgeria furcata with elaterophones × 10; R. Asterella × 5.
|46.||Thallus of one cell in thickness, with a thicker vein||Dendroceros|
|Thallus several cells thick without a vein||47|
|47.||True spiral elaters present in the capsule||Megaceros|
|Pseudoelaters present in the capsule||48|
|48.||Capsule walls with stomata (Figs. 14, 20)||Anthoceros|
|Capsule walls without stomata||Aspiromitus|
|49.||Thallus divided into layers of different tissue with pores from air-cavities||50|
|Thallus not divided into layers, and without pores and air-cavities||55|
|50.||Archegonial group terminal, enclosed in two scales (Fig. 18)||Targionia|
|Archegonia on peduncled receptacles (carpocephala)||51|
|51.||Involucre with one capsule, dehiscing by the falling of a lid, leaving a cup||52|
|Involucre with a group of capsules (one, with infertile archegonia in Lunularia) dehiscing by 4-8 valves||54|
|52.||Carpocephalum dorsal, involucres ascending with a vertical aperture, ventral scales large, hyaline-tipped, upper projecting beyond the margin (Fig. 24)||Plagiochasma|
|Carpocephalum terminal, ventral scales not hyaline-tipped||53|
|53.||Involucres 2-valved, no perianth (Figs. 16, D, 23)||Reboulia|
|Involucres not 2-valved, a white basket-like perianth present, split into fimbriae (Figs. 17, 30 R)||Asterella|
|54.||Peduncle not grooved, gemmae cups lunate, fruiting plants very rare (Fig. 16 E, 26)||Lunularia|
|Peduncle grooved, gemmae cups round when present (Fig. 21)||Marchantia|
|55.||Thallus sometimes gigantic, densely rhiziferous, archegonia terminal, capsule 1-valved splitting on one side and opening till flat (Fig. 25)||Monoclea|
|Archegonia not terminal, capsule dehiscing by 4 valves (Jung. anacrogynae)||56|
|56.||Sexual organs from the upper surface of the frond||57|
|Sexual organs not from the upper surface||62|
|Sterile and female frond not lamellate||59|
|58.||Frond roundish, perianth with a wide mouth||Petalophyllum|
|Frond elongate, sectioned off into succubous lobes, with a lamella at the dorsal base of each, perianth none||Treubia|
|59.||Involucre of laciniate scales, perianth present||60|
|Involucre of laciniate scales, perianth absent||61|
|60.||Stipules and elaterophores absent (Fig. 28)||Pallavicinia|
|Stipules and elaterophores present||Calycularia page 29|
|61.||Invol. scales at the lower base of the calyptra only, calyptra fleshy, no elaterophores (Fig. 27)||Symphyogyna|
|Scales forming a (more or less) complete ring, large and much lacerated, calyptra shortish, sub-globose, elaterophores present||Allisonia|
|62.||Sporophyte ventral, but just below the membraneous expansion, or at the lower fork, involucre and perianth present (Fig. 29)||Hymenophytum|
|Sporophyte not basal, perianth absent||63|
|63.||Sexual organs on short ventral branches, frond margins often ciliate, cells unistratose except at midrib (Figs. 13A, 22, 30 Q)||Metzgeria|
|Sexual organs on short marginal branches, not ciliate, cells usually multistratose, no mid-rib (Fig. 19)||Riccardia|
The ever-increasing genera of this family are in some cases imperfectly understood and hard to separate. It is doubtful if both Drepanolejeunea and Harpalejeunea are present in New Zealand, as recorded by Stephani. Physocolea and Leptocolea were originally divisions of Spruce's sub-genus Cololejeunea. These two divisions are now treated as genera, but the original name of “Colojeunea” has been substituted for that of “Physocolea,” as used by Stephani, and Herzog.*
Key To New Zealand Genera
|2.||Stipules duplicated, one for every leaf||3|
|One stipule for every two leaves||4|
|3.||Dorsal lobe bigger than the ventral, not papillose||Diplasiolejeunea|
|Ventral lobe bigger than the dorsal—a tubular lobule, widening out into a large sack, strongly papillose||Colura|
|4.||Stipules entire, not bifid nor two-lobed||5|
|Stipules bifid or two-lobed||9|
|5.||Lobules and apex of leaves and stipules toothed (rare)||Ptychanthus|
|Leaves and stipules not toothed||6|
|6.||Perianth 3-gonous, leaves densely imbricated, stems noticeably constricted at intervals, stipules narrowed to the base||Thysananthus|
|Perianth not 3-gonous, leaves not usualy densely imbricated, stipules rounded to the base||7|
|7.||Plants large, usually dark green drying to dingy brown, leaves fairly round (moist), perianth not immersed, oblong, dorsally flat with ribs||Archilejeunea|
|Plants smaller, perianth immersed or slightly emergent||8page 30|
|8.||Leaves drying to glossy brown, sub-falcate, perianth dorsally flat and round, margins toothed or leafy, with innovations||Lophololejeunea|
|Leaves yellow-brown, squarrose when moist, perianth globose, deeply 10-keeled with no innovations||Ptychocoleus|
|9.||Plants filiform, white, leaves scarcely contiguous, to remote||10|
|Plants small to medium, leaves usually imbricate or subimbricate||12|
|10.||Leaves obtuse, stipules round||Microlejeunea|
|Leaves acute to acuminate, triangular in general outline, erecto-patent, stipules broader at the apex of the segments||11|
|11.||Stipule segments obtuse, sinus shallow||Harpalejeunea|
|Sipule segments acute, widely diverging||Drepanolejeunea|
|12.||Leaves with high papillae, whitish, usually on filmy ferns||Trachylejeunea|
|Leaves not, or lowly papillose||13|
|13.||Leaves and lobules 2-3 times longer than broad||14|
|Leaves rarely more than 1½ times longer than broad||15|
|14.||Leaves narrowly obovate or sub-lanceolate, margins crenulate, perianth with a long neck (common)||Siphonolejeunea|
|Leaves squarrose, narrow-oblong, concave, cells large, irregular, thick-walled (rare)||Leptolejeunea|
|15.||Ventral margin of the lobe with no indentation at the junction with the lobule, enlarged cells (ocelli) present, perianth dorsally compressed||Rectolejeunea|
|Lobule not in a straight line with the ventral margin of the lobe, (except perhaps in Lejeunea), perianth not dorsally compressed||16|
|16.||Leaf-apex usually acute, decurved (Fig. 3)||Strepsilejeunea|
|17.||Lobule small, cells transparent without trigones (Fig. 15)||Lejeunea|
|Lobule medium to large, trigones present||18|
|18.||Perianth smooth, inflated, with repeated innovations (Fig. 30N)||Taxilejeunea|
|Perianth 5-keeled, lobule involute (more or less) cylindric, plants paler||Pycnolejeunea|
|19.||Minute, lobule large (comparatively), sub-globose, perianth 5-plicate, papillose||Cololejeunea|
|Small, whitish, lobule flat, 2-3-dentate, perianth compressed, obcordate, plants not papillose||Leptocolea|
A Glossary of Terms Used in This Paper.
- Antheridium, the organ containing the male cells.
- Archegonium, a flask-shaped organ containing the embryo sporophyte, (Fig. 27).
- Axil, the angle between the stem and a leaf.
- Bifid, 2-cleft to half-way or thereabouts, (Fig. 11).
- Capsule, the sporangium or terminal portion of the sporophyte which actually contains the spores, (Figs. 9, 25).
- Carpocephalia. See receptacle.
- Calyptra, the inmost protective covering of the sporophyte, being the remains of the archegonium. Always present in the fructification, though sometimes fused with the perianth, (Fig. 19).
- Cauline, pertaining to the stem, used of leaves and stipules in contradistinction to those of the involucre.
- Chloroplast, a green body in plant cells.
- Ciliate, fringed with cilia or hair-like outgrowths, (Fig. 22).
- Columella, the central column in the capsule of the Anthocsrotaceae.
- Complicate, folded together.
- Cuspidate, terminating in a sharp rigid point cr cusp.
- Decurved, bent towards the ground or ventral aspect. (Fig. 3).
- Dehiscing, the opening of the capsule in different ways to let the spores escape, (Fig. 20).
- Dorsal, the front side of a leaf or stem, or that further from the ground or substratum, antical, (Fig. 2).
- Elaters, long and slender single or compound cells mixed with the spores, with spiral thickenings in their walls, (Fig. 13, A, B, C).
- Elaterophores, elaters, maybe of a different shape which remain fixed in a tuft at the base of the capsule in Pelliaceae, or at the top of the valves in Riccardia and Metzgeria, (Fig. 30, Q.).
- Emergent, used in speaking of a perianth which is partly concealed by the involucral leaves.
- Entire, stipules without an apical sinus in Frullania and Lejeunea, or any margin without projections or incisions.
- Epidermis, the uppermost layer of cells of a thallus.
- Evanescent, of short duration.
- Falcate, sickle-shaped.
- Fimbriae, narrow processes.
- Flagelliferous, bearing longly attenuated branches.
- Foliose, with leaves, used of hepatics as opposed to the thalloid group.
- Globose, globular or spherical.
- Homomallous, descriptive of leaves all pointing in the same direction.
- Hyaline, glassy, transparent.
- Imbricate, overlapping like the tiles of a roof.
- Immersed, descriptive of a perianth that does not protrude beyond the involucral leaves.
- Incubous, when the leaf is so inserted that the dorsal margin overlaps the ventral of the leaf above it, (Figs. 4 and 5).
- Infra-Axillary, branches contiguous to the outer base of the leaves.
- Innovations, shoots which arise from below the perianth.
- Intra-Axillary, when the branches spring from the inside of the leaf-axil.
- Involucre, the outermost protective covering of the sporophyte, in the thalloid hepertics a ring or cylinder of tissue, or scales; in the foliose, consisting of enlarged leaves, (Figs. 21, 23).
- Lacerate, jagged or torn.
- Lobule, when the ventral lobe of a leaf is smaller than the dorsal, it is spoken of as the lobule, (Fig. 9).page 32
- Marsupium, a fleshy sack enveloping the sporophyte, serving the purpose of a perianth, (Fig. 6).
- Median, belonging to the middle of a thallus, leaf, etc.
- Multistratose, when cells are arranged in several layers.
- Obovate, inversely ovate, attached by the smaller end.
- Papillae, minute processes arising from the cuticle of the cells.
- Papillose, bearing papillae.
- Perianth, the envelope surrounding the calyptra, (Fig. 8), strictly speaking, formed of united leaves. In the thalloid hepatics often known as the pseudoperianth.
- Plicate, with longitudinal folds.
- Pluriplicate, with many folds or plicae, (Fig. 11).
- Protonema, a simple structure from which the sexual generation is formed.
- Pseudoelaters, a row of irregularly shaped sterile cells, often geniculate, without spiral bands, found in the capsules of Anthoceros, (Fig. 14).
- Receptacle, an elevated and expanded portion of the thallus modified to bear the sexual organs, = carpocephalum.
- Rhiziferous, bearing rhizoids.
- Rhizoids, long hairlike outgrowths, resembling rootlets, (Fig. 15).
- Seta, the stalk of the capsule.
- Sinus, the notch, acute to lunate, between two points.
- Sporophyte, the asexual generation consisting of the capsule (sporangium), its seta and base, sometimes called the sporogonium.
- Squarrose, set at right angles to the stem.
- Stipules, the third or ventral row of leaves sometimes called amphigastria or underleaves, (Fig. 1).
- Stomata, openings through the epidermis of the capsule in Anthocerotaceae, bounded by 2 guard-cells.
- Succubous, when the leaf-base is so inserted that the dorsal margin of the leaf overlaps the ventral margin of the leaf below it, (Fig. 7).
- Terminal, proceeding from the apical cell of stem or thallus, (Fig. 10).
- Thalloid, consisting of or resembling a thallus, frondose.
- Thallus, a flat vegetative structure not differentiated into stem and leaves.
- Transverse, when the leaf insertion is straight across the stem.
- Trigones, thickenings of the walls where 3 or more cells meet, (Fig. 15).
- Trigonous, 3-angled.
- Unistratose, arrangement of cells in one layer.
- Undulate, wavy.
- Ventral, the back side of leaf or stem, or that facing the ground or substratum.