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Tuatara: Volume 12, Issue 1, March 1964

Revised Generic Keys to the Hepatic Flora of New Zealand — With Introduction and Relevant Notes

Revised Generic Keys to the Hepatic Flora of New Zealand
With Introduction and Relevant Notes

Part 2
(continued from Vol. 11, p. 207)

Key to Genera of Lejeuneaceae

1 Underleaves present — 2
Underleaves absent or represented by a few cells, plants very small, whitish — 19
2 Underleaves duplicated, one for every leaf, plants very small 3
One underleaf for every two leaves, plants minute to large 4
3 Leaves distant, dorsal lobe bigger than the ventral, not papillose, leaves roughly four-sided Diplasiolejeunea
Ventral lobe bigger than the dorsal, a tubular lobule widening out into a large sac when moistened, papillose Colura
4 Underleaves entire at the apex, not bilobed nor bidentate, plants medium to large, never whitish (in New Zealand) — 5
Underleaves bifid or bilobed — 9
5 Lobules and apices of leaves and underleaves toothed, known only from the type of P. stephensonianus Ptychanthus page 2
Leaves and underleaves not toothed — 6
6 Gold to brown, perianth three-sided and three-gonous, more or less emergent, monoicous, usually with one sub-floral innovation, leaves densely imbricate, apices folded under, underleaves narrowed towards the base, male stems constricted at intervals, stems with a hyaloderm Thysananthus
Perianths not three-sided, leaves not so densely imbricated, underleaves broad at the base — 7
7 Plants large, drying to dingy brown, leaves more or less rounded, apices folded under, perianths not immersed or emergent, flattened, with no conspicuous keel, but with at least three ribs on both dorsal and ventral faces with two sub-floral innovations, oil bodies very small and numerous Archilejeunea
Plants usually smaller, perianth immersed or slightly emergent, branching intercalary, no sub-floral innovations 8
8 Leaves glossy brown, not squarrose, sub-falcate in L. plicatiscypha, convex with dorsal margins slightly reflexed in L. colensoi, perianth round and compressed, dorsal face smooth, margins and ventral keels toothed in L. plicatiscypha, somewhat foliose in L. colensoi, no innovations below archegonial groups Lopholejeunea
Leaves yellow-brown, squarrose when moist, perianth globose, immersed, strongly keeled with ca. 10 keels, terminal on short branches Ptychocoleus
9 Leaves and underleaves ciliate, lobules saccate Jubula
Leaves and underleaves never ciliate, nor are lobules saccate 10
10 Plants filiform, white, leaves scarcely contiguous to remote 11
Plants small to medium, leaves usually imbricate or subimbricate except in Siphonolejeunea and Leptolejeuna (in New Zealand) — 12
11 Leaves obtuse, lobules half as large as the leaves, perianths very large for size of plants, underleaves circular, cells minute (M. colensoi) Microlejeunea
Leaves acute to acuminate, triangular in general outline, erecto-patent, underleaves broader at the apex of the segments, medulla of stem consisting of three longitudinal rows Drepanolejeunea
12 Leaves hyaline to dingy white, falcate, dorsal margin and apex often obliquely folded under, showing the characteristic high papillae at the fold, underleaves with each segment page 3 about as wide as the stem, perianths on short lateral branches, rectangular with one median rib on both dorsal and ventral faces, straight across the top, often growing with Leptocolea on filmy ferns Trachylejeunea
Leaves not highly papillose — 13
13 Leaves 2-3 times longer than broad — 14
Leaves rarely more than 1½ times longer than broad — 15
14 Plants usually pale green to whitish, leaves distant, narrowly obovate, lobule elongate, narrow, perianth with a long neck, cells uniform, may be gemmiferous Siphonolejeunea
Plants brown, pinnately branched, stem and branches prostrate on the substratum (in plants seen), leaves narrow oblong, cells irregular with large ones (ocelli) interspersed, thick-walled, lobule large, carina arched Leptolejeunea
15 Ventral leaf-margin with no indentation at the junction with the lobule, small, whitish, enlarged cells (ocelli) present, perianth compressed with no dorsal keel Rectolejeunea
Fold of the lobule not in a straight line with the ventral margin of the lobe (except perhaps in Lejeunea) perianth not dorsally compressed, usually five-keeled — 16
16 Hyaline papilla at the distal base of the apical tooth of the lobule, lobules involute, inflated, horizontally flask-shaped, brown, decurved and acute in Subgenus Strepsilejeunea Cheilolejeunea
Hyaline papilla at the proximal base of the apical tooth of the lobule, or on it, leaves of softish texture, trigones small or absent, lobules strongly apically toothed in Lejeunea helmsiana — 17
17 Leaves closely imbricate, pale and semi-transparent, underleaves large, three times the width of the stem, sinus more or less closed lobule inflated, involute (Pycnolejeunea glauca) Pycnolejeunea
Leaves loosely imbricate hyaloderm present round the stem, perianth normally five-keeled — 18
18 Leaves falcate in L. kirkii, partly clasping the stem in L. flava, perianth inflated with keels obsolete in L. tumida, lobule ca. one-fifth the size of the lobe, underleaves deeply bifid, with segments gaping but not necessarily diverging, cell walls thin Lejeunea
Stem with a sympodial succession of female inflorescences, perianth may be inflated Taxilejeunea page 4
19 Minute, subhyaline, leaves papillose or without papillae, lobule comparatively large, subglobose, perianth five-plicate Cololejeunea
Plants small, whitish, leaves shiny usually recurved, incurved or flexuous when dry, not papillose, perianth compressed, obcordate Leptocolea

Notes

Jubula. couplet 9. This genus which has characters of both Frullania and Lejeunea is now considered to be closer to Lejeunea. The discovery of this genus in Stewart Island by W. Martin, is, I understand, the first in the Southern Hemisphere.

Drepanolejeunea couplet 11. Stephani's Harpalejeunea colensoi is considered to be a Drepanolejeunea.

Leptolejeunea couplet 14. This genus is included on the basis of an identification by the late Dr. Herzog of an undescribed species from Kauri Valley on kie-kie leaf, coll. H. B. Matthews 23/7/20, 36861 AK, locality not stated.

Cheilolejeunea couplet 16. Strepsilejeunea and Euosmolejeunea are now included in Cheilolejeunea. All three were originally Spruce's subgenera of Lejeunea.

Taxilejeunea couplet 18 is retained, not because of Stephani's T. colensoana which is a Lejeunea, but because of an undescribed species, Herzog's T. seriata with a series of perianths and innovations along the stem.

Key to Genera of Lepidoziaceae

1 Leaves all bifid to the base with no basal discus, segments consisting entirely of one row of cells, small underleaves present in our species, branching mainly ventral intercalary (A. herzogii see note) Arachniopsis
Leaves neither bifid to the base, nor all bifid — 2
2 Plants dendroid, apices of stems and branches involute, stems bipinnate, not flagelliform, little distinction between cortex and medulla, medullary cells very numerous in D. insularum, leaves erect, confined to Stewart Island and Fiordland in New Zealand Dendrolembidium
Plants not dendroid, apices of stems and branches not or scarcely involute, hyaloderm of large cells present or absent — 3
3 Leaves all incubous — 4
Leaves otherwise — 9page 5
4 Branching all lateral and intercalary, cell cavities four-angled rectangular to quadrate, walls thick, lowly depressed, very small, stem-leaves three-fid Drucella
Branching and cells otherwise — 5
5 Stems with a hyaloderm, leaves more or less symmetric, cells without thick walls, basal discus always present, branching of mixed types Telaranea
Stems without a hyaloderm unless stated — 6
6 Leaves glaucous, four-lobed, collapsed when dry, cells with thin walls, quadrate, uniform Lepidoziopsis
Leaves not glaucous, (except in Bazzania tayloriana), not altered when dry, cells with thick walls, not uniform in size 7
7 Leaves usually four-lobed, asymmetric, underleaves similar but small and symmetric Lepidozia
Leaves 2-3-lobed or -dentate, rarely entire, underleaves not similar to the leaves — 8
8 Ventral branches from the axils of the underleaves (intercalary) leaves sublongitudinally inserted, more or less at right angles to the stem, branching often dichotomous Bazzania
Ventral branches from alongside the underleaves (terminal), leaves bilobed, lobes unequal Section inaequilatera of Acromastigum
9 Leaves transverse, flattish, underleaves entire, ventral branches from beside the underleaves (terminal) Section squarrosa of Acromastigum
Leaves transverse or succubous, ventral branches from the axils of the underleaves (intercalary) — 10
10 Leaves transverse, concave, mostly complicate, shortly bilobed or entire, branching mostly ventral, hyaloderm present (in type), leaves tri-lobed in L. berggrenii (rare) Lembidium
Leaves deeply 4-5-lobed — 11
11 Stems very slender with a hyaloderm, leaves minute, usually five-lobed, succubous, the dorsal portion transverse, apical spines long, single-celled, at right angles to the rest of the leaf and parallel to the stem, branching both lateral, terminal and ventral intercalary, branches may be flagelliform Psiloclada
Small, leaves transverse, deeply four-lobed, several rows of geminate cells in lobes (in New Zealand), branching lateral terminal of Microlepidozia type (see glossary) Microlepidozia
page 6

Notes

Arachniopsis couplet 1. It is now accepted that Lepidozia herzogii, with a complete absence of a basal discus in the leaf, is an Arachniopsis. Evans (1939) placed this genus in the Cephaloziaceae, but its non-exclusively ventral branching, and the fusiform-cylindrical (not trigonous) perianth are characteristics of the Lepidoziaceae. The sporophyte of Arachniopsis has not yet, I think been investigated morphologically.

With the introduction of Arachniopsis to the New Zealand flora, the transference of Lepidozia herzogii to this genus is made accordingly.

Arachniopsis herzogii (Hodgson) Hodgson comb. nov. Type: From Russel. Bay of Islands, North Island, leg. V. W. Lindauer (No. 281).

Lepidozia herzogii Hodgson Trans. Roy. Soc. N.Z., 78, 500, 1950, nom. nov. pro L. bisetula Herzog, Trans. Roy. Soc. N.Z., 68, 44, 1938, non L. bisetula Stephani, Spec. Hep., vi, 323, 1924.

Telaranea herzogii (Hodgson) Hodgson Rec. Dom. Mus., 4, 11, pp. 101-132. 1962.

Anthocerotopsida

The class Anthocerotopsida which includes five or six genera, according to opinion, is represented by about 300 species, comprising one order Anthocerotales.

Anthocerotales

Plants (gametophytes) thalloid, dorsiventral, lobed, internal tissues not differentiated. Rhizoids small, smooth-walled, ventral scales absent. Air-chambers and pores absent. Cells usually each with a single chloroplast with a pyrenoid. Antheridia endogenous in closed cavities on the thallus. Archegonia sunk in the tissue of the thallus. The sporophyte indeterminate in growth, consists of a foot, an intercalary meristematic region and a long cylindrical capsule with a central columella. Stomata present in the capsule wall. Capsule splitting along one side and liberating the spores.

Family Anthocerotaceae, Anthoceros, Phaeoceros, Megaceros, Dendroceros.

Key to Genera of Anthocerotopsida

1 Elaters with spiral thickenings, spores containing chloroplasts, stomata absent from the epidermis of the capsule, sheath of sporophyte relatively long, one antheridium in each antheridial cavity — 2page 7
Elaters without spiral thickenings, spores without chloroplasts, stomata present in the epidermis of the capsule, more than one antheridium in each cavity, sporophyte sheath relatively short — 3
2 Thallus strap-shaped with a wide and thick midrib with unistratose frilly marginal wings, spores sometimes multicellular, may grow on trees Dendroceros
Thallus rosette-shaped, apparently multistratose throughout, grows on ground or rotting logs Megaceros
3 Thallus containing large slime cavities, antheridium jacket with four tiers of cells, spores dark brown to black Anthoceros
Thallus without large cavities, cells of antheridium jacket not clearly arranged in four tiers, spores translucent, yellow Phaeoceros

Glossary

  • Antheridium, the organ containing the male cells.
  • Archegonium, a flask-shaped organ containing the egg and later the embryo sporophyte.
  • Axil, the angle between the stem and leaf.
  • Bifid, two-cleft to half-way or thereabouts.
  • Bract, a specialized leaf associated with the sex organs.
  • Bracteole, an underleaf in an inflorescence.
  • Capsule, the sporangium or terminal portion of the sporophyte which actually contains the spores.
  • Coelocaule, a thick-walled prolongation of the stem tissue (stem perianth or perigynium) usually studded with paraphyllia.
  • Calyptra, the innermost protective covering of the sporophyte, being the remains of the archegonium. Always present in the fructification, though sometimes fused with the perianth.
  • Carpocephalum, see receptable.
  • Cauline, pertaining to the stem, used of leaves and underleaves in contradistinction to those of the involucre (bracts).
  • Chloroplast, a green body in plant cells.
  • Ciliate, fringed with cilia or hair-like growths.
  • Columella, the central column in the capsule of the Anthocerotopsida.
  • Complicate, folded together.
  • Cortex, the outermost layer or layers of cells in the stem.page 8
  • Cuspidate, terminating in a short rigid cusp or point.
  • Dehiscing, the opening of the capsule in different ways, to let the spores escape.
  • Dendroid, like a tree.
  • Dichotomous, forked several times with equal forks.
  • Distal, of the hyaline papilla in Lejeuneaceae, outside the free apical angle of the lobule.
  • Dorsal, the front side of a leaf or stem, or that further from the ground or substratum.
  • Dorsiventral, pertaining to an organ having distinct dorsal and ventral surfaces which usually show differences in structure.
  • Elaters, long and slender single or compound cells mixed with the spores, with spiral thickenings in their walls.
  • Elaterophores, elaters, sometimes differing in shape from the last, 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.
  • Emergent, descriptive of a perianth which is partly concealed by the involucral leaves (bracts).
  • Endogenous, development from a deep seated layer.
  • Entire, of underleaves without an apical sinus in Frullania and Lejeuneaceae or of any margin without projections or incisions.
  • Epidermis, the uppermost layer of cells in a thallus.
  • Evanescent, of short duration.
  • Falcate, sickle-shaped.
  • Fimbriae, narrow processes.
  • Flabellate, fan-shaped.
  • Flagella, filiform branches.
page 9
Plate 1 1. Diplasiolejeunea lyratifolia ventral, showing duplicated underleaves, one for each leaf (2 inadvertantly omitted) × 10. 2. Diplophyllum domesticum dorsal, showing small dorsal leaf-lobes × 5. 3. Cheilolejeunea sp. (subgenus Strepsileieunea) ventral, showing acute decurved leaf apices × 10. 4. Bazzania novae-zelandiae ventral, showing incubous leaves and ventral axillary branching (intercalary) × 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. Telaranea tetradactyla dorsal, showing deeply divided leaves and lateral perianth × 8. 9. Radula strangulata ventral showing lobules, absence of underleaves, and spent capsule × 10. 10. Lophocolea sp. dorsal showing terminal perianth with 3rd. keel dorsal, and bracts, × 5. 11. Cephaloziella sp. showing deeply pluriplicate perianth with large bracts, and bifid, transverse leaves × 12. 12. Goebeliella cornigera ventral, showing entire underleaves and double lobules. 13. Elaters, A, Metzgeria furcata monospiral, × 125; B, Frullania rostellata monospiral; C, Radula stragulata bispiral. 14. Pseudoelaters of Anthoceros × 100. 15. Cells of Lejeunea sp. without trigones ca 40 microns. 16. Rhizoids; D, Rebou'la hemisphaerica, smooth; S. Lunularia cruciata tuberculate, × 125.

Plate 1
1. Diplasiolejeunea lyratifolia ventral, showing duplicated underleaves, one for each leaf (2 inadvertantly omitted) × 10. 2. Diplophyllum domesticum dorsal, showing small dorsal leaf-lobes × 5. 3. Cheilolejeunea sp. (subgenus Strepsileieunea) ventral, showing acute decurved leaf apices × 10. 4. Bazzania novae-zelandiae ventral, showing incubous leaves and ventral axillary branching (intercalary) × 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. Telaranea tetradactyla dorsal, showing deeply divided leaves and lateral perianth × 8. 9. Radula strangulata ventral showing lobules, absence of underleaves, and spent capsule × 10. 10. Lophocolea sp. dorsal showing terminal perianth with 3rd. keel dorsal, and bracts, × 5. 11. Cephaloziella sp. showing deeply pluriplicate perianth with large bracts, and bifid, transverse leaves × 12. 12. Goebeliella cornigera ventral, showing entire underleaves and double lobules. 13. Elaters, A, Metzgeria furcata monospiral, × 125; B, Frullania rostellata monospiral; C, Radula stragulata bispiral. 14. Pseudoelaters of Anthoceros × 100. 15. Cells of Lejeunea sp. without trigones ca 40 microns. 16. Rhizoids; D, Rebou'la hemisphaerica, smooth; S. Lunularia cruciata tuberculate, × 125.

page 10
  • Flagelliferous, bearing longly attenuated, or flagelliform branches.
  • Foliose, with leaves, used of leafy hepatics as opposed to the thalloid group.
  • Frullania-Type of branching, a pattern of terminal branching in which the branch initial proceeds from the ventral half of the lateral segment of the apical growing point.
  • Fusiform, tapering at both ends as in a spindle.
  • Gemma, a small, usually deciduous body which propagates the hepatic asexually.
  • Gemmiferous, bearing gemmae.
  • Globose, globular or spherical.
  • Hyaline, glassy, transparent.
  • Hyalodermis or Hyaloderm, a unistratose cortex of comparatively few, large, thin-walled cells.
  • Imbricate, overlapping like the tiles of a roof.
  • Immersed, descriptive of a perianth that does not protrude beyond the bracts.
  • Incubous, descriptive of leaves inserted so that the dorsal margin of each leaf overlaps the ventral margin of the leaf above it.
  • Inflorescence, the reproductive portion of a plant together with the usually modified parts surrounding it.
  • Innovation, a shoot growing out from below a female inflorescence.
  • Intercalary, of branching in which the branch initial does not arise from the apical cell, may be lateral or ventral.
page 11
Plate 2 17. Asterella australis × 1½, F, carpocaphalum showing laciniate perianth with laciniae cohering at the apex × 4. 18. Targionia hypophylla with terminal valves × 1½. 19. Ricardia marginata showing absence of nerve, and lateral calyptra × 3. 20. Anthoceros sp. with linear dehiscing capsule, nat. size. 21. Marchantia berteroana with male carpocephalum and rounded gemmae cups; G, female carpocephalum showing involucres between the rays, nat. size. 22. Metzgeria furcata dorsal with ventral calyptras showing, also midrib and ciliate margins; H. ventral with male branches × 4. 23. Reboulia hemisphaerica, carpocephalum, underneath view, showing bi-valved involucres × 2½. 24. Plagiochasma australe with invol. lobes opening vertically × 1½. 25. Monoclea forsteri with capsule splitting on 1 side only ½ nat. size. 26. Lunularia cruciata with lunate gemmae cups nat. size. 27. Symphyogyna hymenophyllum showing invol. scales and calyptras; 1, sterile archegonia adhering to calyptra × 2. 28. Pallavicinia lyellii, J, invol. cup; K, pseudoperianth with calyptra included nat. size. 29. Hymenophytum phyllanthus, L, basal ventral invol. cup; M, pseudoperianth, calyptra included, nat. size. 30. Dehiscent capsules; N, Taxilejeunea sp. showing valves not divided to the base × 10; O. Plagiochila × 7; P. fossombronia × 7; Q, Metzgeria with elaterophores × 10; R, Asterella × 5.

Plate 2
17. Asterella australis × 1½, F, carpocaphalum showing laciniate perianth with laciniae cohering at the apex × 4. 18. Targionia hypophylla with terminal valves × 1½. 19. Ricardia marginata showing absence of nerve, and lateral calyptra × 3. 20. Anthoceros sp. with linear dehiscing capsule, nat. size. 21. Marchantia berteroana with male carpocephalum and rounded gemmae cups; G, female carpocephalum showing involucres between the rays, nat. size. 22. Metzgeria furcata dorsal with ventral calyptras showing, also midrib and ciliate margins; H. ventral with male branches × 4. 23. Reboulia hemisphaerica, carpocephalum, underneath view, showing bi-valved involucres × 2½. 24. Plagiochasma australe with invol. lobes opening vertically × 1½. 25. Monoclea forsteri with capsule splitting on 1 side only ½ nat. size. 26. Lunularia cruciata with lunate gemmae cups nat. size. 27. Symphyogyna hymenophyllum showing invol. scales and calyptras; 1, sterile archegonia adhering to calyptra × 2. 28. Pallavicinia lyellii, J, invol. cup; K, pseudoperianth with calyptra included nat. size. 29. Hymenophytum phyllanthus, L, basal ventral invol. cup; M, pseudoperianth, calyptra included, nat. size. 30. Dehiscent capsules; N, Taxilejeunea sp. showing valves not divided to the base × 10; O. Plagiochila × 7; P. fossombronia × 7; Q, Metzgeria with elaterophores × 10; R, Asterella × 5.

page 12
  • Involucre, the outermost protective covering of the sporophyte, in the thalloid hepatics, a complete or incomplete ring or cylinder of tissue, or scales, in the foliose, consisting of enlarged leaves (bracts).
  • Lacerate, jagged or torn.
  • Lamellate, bearing plates of tissue (lamellae).
  • Lobule, usually thought of as the ventral lobe in a two-lobed leaf.
  • Marsupium, a fleshy sack enveloping the sporophyte, serving the purpose of a perianth.
  • Medulla, the central region of the stem.
  • Meristematic, capable of active cell-division.
  • Microlepidozia-Type of branching, a pattern of branching where, in addition to the branches arising from the ventral half of a lateral segment of the pyramidal apical cell, they may arise also from the dorsal half of the lateral segment.
  • Monoicous, having both archegonia and antheridia on the same plant.
  • Multistratose, of a flat organ having more than one layer of cells.
  • Obcordate, inversely cordate.
  • Obovate, inversely ovate, attached by the smaller end.
  • Paraphyllia, minute leaf-like or scale-like organs on a stem or coelocaule.
  • Papillae, minute processes arising from the cuticle of the leaves.
  • Papillose, bearing papillae.
  • Perianth, the envelope surrounding the calyptra, strictly speaking, formed of united leaves. In the thalloid hepatics, often known as the pseudoperianth.
  • Perigynium, a fleshy cup or tube formed of the thickened, hollowed out end of the stem, containing the sporophyte, fused with the perianth in Isotachis.
  • Peristome, the fringe of teeth surrounding the mouth of the capsule of a moss.
  • Plicate, with longitudinal folds.
  • Pluriplicate, with many folds or plicae.
  • Protonema, a simple early stage of the sexual generation.
  • Proximal, of the hvaline papilla in Lejeuneaceae, inside the free apical angle of the lobule.
  • Pseudoelaters, a row of irregularly shaped sterile cells, often geniculate, without spiral bands, found in the capsules of Anthoceros.
  • Radial, spreading from a common axis or centre.
  • Receptacle, an elevated and expanded portion of the thallus, modified to bear the sexual organs.
  • Rhiziferous, bearing rhizoids.
  • Rhizoids, long hairlike outgrowths resembling root hairs.
  • Saccate, pouched.page 13
  • Secund, curving over to one side only.
  • 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 call the sporogonium.
  • Stylus, a more or less triangular projection between the stem and ventral lobule in the genus Frullania.
  • Squarrose, of leaves, set at right angles to the stem.
  • Stomata, openings through the epidermis of the capsule in Anthocerotaceae, bounded by two guard-cells.
  • Succubous, descriptive of leaves in which the leaf-base is so inserted that the dorsal margin of each leaf overlaps the ventral margin of the leaf below it.
  • Terminal, proceeding from the apical cell of stem or thallus, from lateral or ventral segments.
  • Thalloid, consisting of, or resembling a thallus, frondose.
  • Transverse, descriptive of a leaf-insertion which is crosswise on the stem, as distinct from a diagonal insertion.
  • Trigones, thickenings of the walls where three or more cells meet.
  • Trigonous, three-angled.
  • Unistratose, one-layered, of cells.
  • Undulate, wavy.
  • Ventral, the back side of a leaf or stem, or that facing the ground or substratum.
  • Vitta, a band or area of elongated or enlarged cells usually with thicker walls.