The sporeling development in Frullania tamarisci (L.) Dum

Abstract

The sporeling development in Frullania tamarisici (L.) Dum. ssp. tamarisci is described for the first time. Its pattern belongs to the Frullania-type in which a globose, many-celled protonema is formed within the stretched exospore. The primary leaves are ovate to oblong, followed by the saccate-inflated juvenile leaves. In the juvenile stage each underleaf is associated with a single leaf.     

Two new species of Lejeunea Lib. (Hepaticae: Lejeuneaceae) from Sikkim,India

Abstract

Two new species of Lejeunea Lib., L. kashyapii sp. nov. and L. mehrana sp. nov. are described from Sikkim, India. The former is characterized by sub-orbicular leaves; first tooth of leaf lobule, 1–3 cells long 1–2 cells wide at base; reniform underleaves slightly wider than long; monoicous sexuality; 2–3-paired male bracts; obcordate perianth with 4–5 smooth keels (2 lateral, auriculate; 2 ventral; 0–1 dorsal, indistinct). Whereas, the latter is characterized by oblong – ovate leaves; lobule 1/6–1/5 as long as lobe; distant – contiguous underleaves with 1–3 teeth on each lobe; dioicous (?) sexuality; 2–4-paired male bracts and 1–2 male bracteoles present near the base of androecia. A key to the Indian species of the genus are provided.     

Spore germination and sporeling developlnent in Jungermannia sphaerocarpa Hook.

Abstract

The globular protonema of Jungermannia sphaerocarpa developed outside the spore wall in axenic culture. Up to six gametophytes were produced by each protonema, and sporeling development to the attainment of sexual maturity is described. Significantly fewer and larger oil bodies occurred in the rounded mature leaves compared with bifid immature leaves and with cells of the protonema. Within the numerous rhizoids, an intense purple pigmentation was developed and maintained.     

PHOTOTROPISM OF SELAGINELLA: THE DIFFERENTIAL RESPONSE TO LIGHT

Selaginella kraussiana (Kunze) A. Braun has a plagiotropic dorsiventral stem with two rows of small leaves on the dorsal surface and two rows of large leaves inserted laterally. Stem tips exhibit a differential phototropic response. When stem tips are placed in their normal horizontal orientation and the dorsal surfaces are illumianted, the tips bend only 20” below the horizon and away from light. Stem curvature is limited to a zone 450 μm long located 1.5 mm behind the shoot apex. The dorsal cortical cells within this zone of curvature are about 1.44 times longer than the ventral cortical cells. Illumination of the ventral surface of the stem tips elicits a strong phototropic response. The stems bend from 123–158° below the horizon and toward light, and the zone of curvature increases in length to 10 mm of the explant. The curvature is large enough so that the previously shaded dorsal leaves of the stem tips become redirected toward the light. This phototropic response is promoted by white and blue light, whereas red or far-red light has no effect. When stem tips are cultured in total darkness, the length of the zone of curvature is 8.0 mm but the stems bend only 50–67°. Treatment of the small dorsal leaves with phenylacetic acid inhibits phototropic curvature, and the phototropic response is unaffected by gravity.     

DEVELOPMENTAL ANATOMY OF JUVENILE AND ADULT SHOOTS OF MARCGRAVIA RECTIFOLIA L

Marcgravia rectifolia L. is a dimorphic vine having distinct juvenile and adult shoots. The juvenile shoot is a climber characterized by an orthotropic growth habit, a flattened stem, adventitious roots, and ovate leaves. The adult shoot, on the other hand, possesses a plagiotropic growth habit, has a cylindrical stem, few or no adventitious roots, and lanceolate leaves. Both phases have distichous phyllotaxy, however the plastochron is shorter for the adult phase than for the juvenile. Internode elongation occurs earlier for adult shoots than for juvenile shoots. Cytological analyses show the flattened stem of the juvenile results from differential production of cells, especially in the pith region. On the other hand, internodes of the adult phase are longer than juvenile internodes, a result of more cells produced rather than longer cells. In juvenile stems a perivascular band of elongated fibers develops, while in adult stems this band consists of brachyosclereids. Both phases undergo secondary growth and have non-storied cambia. Cambial activity begins in the 6th internode of each phase. As secondary growth proceeds, the adult stem produces much more xylem than juvenile stems of the same age. Adventitious roots produced in the juvenile stem are located in vertical rows at the “corners” of flattened stems and are attachment structures aiding the climbing habit of this vine. Phase changes occur regularly in this species. The juvenile phase usually transforms into the adult, however the adult phase can spontaneously revert back into the juvenile phase. The anatomical features and the phase changes are discussed and compared to Hedera helix, a vine whose phase changes have been studied in some detail. It is suggested that the anatomical features of Marcgravia rectifolia L. including its phase changes, may provide an alternative system to study physiological changes similar to those done with Hedera helix.     

Scapania mucronata Buch in Scotland

Abstract

Regeneration from detached leaves at 20°C in 12 h days was studied in six species. Of the four species of Polytrichum and two of Pogonatum studied, only Pogonatum aloides did not regenerate from leaves. This result could be related to the fact that in nature only this species possesses persistent primary protonemata. Polytrichum commune, P. formosum and P. juniperinum developed long, muchbranched secondary protonemata which produced buds at intervals. Pogonatum urnigerum developed buds without an initial protonema, and Polytrichum piliferum short, unbranched protonemal threads, each bearing a single terminal bud. In all cases regenerants arose from either the large cells at the bases of lamellae, or less often, basal cells of the lamellae themselves. In Pogonatum urnigerum the amount of regeneration tended to decrease from apex to base of leaf, while in the Polytrichum species the reverse occurred. No definite conclusions could be drawn with regard to the effect, if any, of leaf age on regeneration. Possibly the temperature experienced beforehand or some other seasonal factor, affects regeneration, but the question needs further investigation.     

Germination of the Spores and Development of Primary and Secondary Protonema of Funaria hygrometrica

Abstract

1. The primary protonema of Funaria hygrometrica, cultivated on Knop's or Marchal's agar in the light, proved to consist of filaments with much chlorophyll, a hyaline membrane, perpendicular cross-walls and branches equal to the main filament (chloronema). These filaments grow on the surface of the agar, the branches may also grow vertically. Sometimes filaments with less chlorophyll occur immediately after the germination. The caulonema described by Sironval has not been observed. Thus the rhizoid-like forms mentioned in the literature should more likely be considered as a result of external conditions (see Schoene, Bauer, Heitz and Fitting). Therefore it remains doubtful if a distinction between rhizoids and chloronema on the primary protonema is of any importance as it is impossible to give a good definition of either form.

At the base of moss plants main filaments with brown membranes, oblique septa and without chlorophyll may develop (rhizoids). They grow on the surface or within the agar. In F. hygrometrica especially, the stem seems to influence the occurrence of these rhizoids. The main filaments form buds on the basal cell of the branches and thus serve for vegetative reproduction. The branches show the characteristics of the chloronema. This is contrary to the conclusion of Westerdijk that rhizoids would pass into chloronema only when they are damaged or when the growth of the end bud of the plant is inhibited. At the base of the plant, moreover, little ramified, short branches with oblique septa appear which do not produce buds.

2. Branches may develop in the first growth stages of the primary protonema at any point of the cells. One single cell of a main filament can produce none, one, or more than one branch. Later the branches appear immediately behind the acroscopic cross-wall except in a few cases. Each cell then produces one branch.

3. Buds always develop at the basal cell of a primary branch of a green main filament or of a rhizoid derived from a moss plant.

4. In two ways the protonema may fall into pieces, which can develop into new main filaments:

(a) By forming brood cells; rounded cells which get detached by splitting of the septum. This phenomenon is very frequent. Contrary to Servettaz's opinion it seems to occur particularly under unfavourable conditions.

(b) By forming special cells, tmemata, whose walls are rent. These occur on the primary protonema contrary to the observations of Correns and Bauer, but they are much less frequent than the brood cells. No observations have been made on the circumstances of their occurrence.     

An Annotated List of British Hepatica

Abstract

Archidium minutissimum sp. nov., a minute ephemeral species with persistent protonema and red-brown bract-like leaves, is fully described and illustrated.     

Hepatics from Rovno amber (Ukraine), 6. Frullania rovnoi,sp. nov.

A fossil species of the extant liverwort genus Frullania Raddi is described and illustrated, based on a single inclusion in a piece of Rovno amber (Ukraine) that shares its age with Late Eocene Baltic amber, its northern contemporary. Frullania rovnoi is characterised by leaves with a rounded dorsal lobe and the absence of ocelli. The ventral lobe is inflated and forms a saclike lobule, which is bell-shaped and somewhat constricted above the mouth. The bifid underleaves have several blunt teeth or angulations along the shoulder. The Rovno fossil differs sufficiently from morphologically similar species preserved in Baltic and Bitterfeld amber as to be described as new to science. The shape of the lobules and underleaves, as well as the absence of ocelli, indicate an affiliation to F. sect. Australes, hitherto represented in Eocene amber inclusions solely by F. schumannii (Casp.) Grolle. The Rovno fossil is distinguished from extant species of F. subg. Australes and from F. schumannii by having roughly and irregularly dentate-angulate underleaf margins.     

A new Cheilolejeunea Marchantiopsida: Lejeuneaceae from montane forests in New Zealand

Abstract

Cheilolejeunea celata M.Renner & Glenny sp. nov., a minute species from high elevation (generally >600 m), high rainfall forests on the wetter, western side of New Zealand, is described and illustrated. It is similar to Cheilolejeunea novaezelandiae R.M. Schust. in its dome-shaped papillae on the lobe surface and its autoicous state, but differs in bearing papillae over the entire lobe surface and on the underleaves, in having narrower underleaves that are never imbricate and have a narrow sinus, and in growing primarily in forest, on the stems of other bryophyte species. In its combination of oblique lobes, strongly inflated keel, and bifid underleaves, the species provides further support for the recent merger of Cyrtolejeunea into Cheilolejeunea.     

Ptychomitrium subcrispatum Thér. & P.de la Varde,an east southern African species excluded from the Cape Verde bryoflora

Abstract

Pictolejeunea levis, a new species of Lejeuneaceae found in N.E. Cuba, is described and illustrated. The species stands out within Pictolejeunea on account of its smooth leaf cells and the presence of ocelli on dorsal and ventral epidermal cells of the stem. Differences between this and the other four known species in the genus are discussed.     

Tetrameres tarapungae n.sp. (Nematoda: Spirurida), a parasite of the red-billed gull,Larus novaehollandiae scopulinus

Abstract

Tetrameres (Tetrameres) tarapungae n.sp. is described from specimens from the proventriculus of juvenile red-billed gulls from Kaikoura, New Zealand. The male is characterised by having two short rows of lateral cervical cuticular spines that do not extend beyond the middle of the oesophagus, a body length of 2.2–2.6 mm, and the larger spicule longer than half the body length. The male tail bears four pairs of subventral papillae and two pairs of lateral papillae. The pathology of the infections is described briefly.     

中国和越南苔类植物新记录种——柏氏细鳞苔

报道了采自中国广西和越南北部地区细鳞苔属新记录种——柏氏细鳞苔[Lejeunea patersonii(Steph.)Steph.]。该种的主要特征为侧叶顶端圆形或钝形,叶边缘具圆齿;腹叶小,远生,宽为茎的1~2倍;叶细胞角质层平滑,三角体不明显或中等大,中部球状加厚缺。该研究对柏氏细鳞苔与其相似种进行了细致的比较讨论,并对柏氏细鳞苔原有的地理分布信息进行了更正,重新确认了该种的地理分布。     

Applications of Environmental Scanning Electron Microscopy (ESEM) in botanical research

Abstract

Conventional Scanning Electron Microscopy (SEM) is limited by artefacts from sample preparation, while Environmental Scanning Electron Microscopy (ESEM) permits observations of hydrated, non-conductive samples without any preparation. In this short review, the two systems are described and some examples given. In addition, a study of trace element localization by X-ray ESEM microanalysis in Azolla caroliniana cultured in the presence of trace elements is presented. The highest concentration occurred in roots and stem. Leaves showed lower accumulation, with concentrations decreasing from the base to the apex of the shoot, and sharp differences between ventral and dorsal lobes of single leaves, the former accumulating more than the latter. The epidermal cells in the ventral lobes of basal leaves were largely lost in treated plants. The differential localisation of trace elements in the plant protected the dorsal lobes, which are the main photosynthetic part of the plant, the nitrogen-fixing cyanobacterial colonies and the apical meristems from potentially adverse effects of trace elements.     

Studies on Antipodal Hepaticae: II. Archeophylla Schuster and Archeochaete Schuster,New Genera of Blepharostomaceae

Abstract

The two genera Archeophylla Schust. and Archeochaete Schust., briefly diagnosed in a key to antipodal Hepaticae (Schuster, 1963 b), are described in detail; for the fint genus a second, new species is described. Archeophylla differs from other genera assigned to the Blepbarostomaceae in broadly unispiral elaters and the development of conspicuous trigones of the leaf cells. Archeochaete shows a series of synthetic features, such as a contracted perianth mouth and quadrifid bracts that lack armed margins, suggestive of Lophochaete Schust.; other features of the genus strongly suggest Temnoma Mitt., e.g. the non-bisbifid leaves and the tendency for smaller underleaves. This last genus was recently erroneously assigned to the Trichocoleaceae by Fulford (1963).

The discovery of these genera strongly indicates that the Blepharostomaceae must be broadly delimited; hence the families Pseudolepicoleaceae and Herzogiariaceae are placed in synonymy. Chaetocolea Spruce is also shown to belong probably to the Blepharostomaccae, in which case the Chaetocoleaceae would also have to be relegated to synonymy.     

Sphagnum olafii (Sect. Acutifolia), a new peat-moss from Svalbard

Abstract

Sphagnum olafii (Sect. Acutifolia) sp. nov. can be recognized in the field by its soft appearance, its brownish capitula with often a faint lustre of purple-red, by a variegated, pale and brownish stem and lingulate-triangular stem leaves. Microscopically, it is recognized by the occurrence of scattered pores in the surface cells of the stem cortex, and markedly bulging hyalocysts on the convex surface of the branch leaves with narrow, wedge-shaped exposures to the chlorocysts. The new species shows closest affinity to S. arcticum Flatb. & Frisv. It is reported from four localities in Svalbard.     

The systematic identity of Chiloscyphus trichocoleoides,a new liverwort species from New Zealand,uncovered by morphological and molecular evidence

Abstract

A new liverwort species from Western Nelson Ecological Province of New Zealand known from a single sterile specimen is described. It is unusual in having well-developed stem paraphyllia, and the leaves and underleaves are divided with three levels of ciliate division in a pinnate manner. This morphology suggested membership of Trichocoleaceae or Trichotemnomaceae, but other features of the plant made placement in either family seem unnatural. We determined its position by conducting phylogenetic analyses of rbcL, rps4 and trnL–F sequence datasets from 35 exemplars, and further confirmation of the position was carried out by an extended analysis using rbcL sequence dataset of 59 exemplars. The surprising result is that it belongs within the genus Chiloscyphus, where it is unique in these features. We describe this new species as Chiloscyphus trichocoleoides. Placing the new species in Chiloscyphus has broadened the generic concept of Chiloscyphus, and its phylogenetic relationship within and to other genera such as Clasmatocolea and Heteroscyphus needs further investigation. The results also show that the same morphological features seen in Chiloscyphus and in Trichocoleaceae and Trichotemnomaceae have developed independently.     

Inter-population variation in morphology and physiology in the cosmopolitan moss Bryum argenteum Hedw.

Abstract

Aspects of the morphology and temperature relations of clones isolated from temperate, tropical and polar populations of Bryum argenteum are compared. The clones were similar in their responses to frost and to high temperature stress, and a day/night temperature regime of 22/15°C in each case proved the most favourable of those tested for protonema growth and shoot production. Antarctic and tropical provenances both showed slow protonema growth and shoot production at 5/–5°C. Antarctic clones were in general the most vigorous of those tested in a range of environments.

The clones proved morphologically distinct from each other in collateral cultivation, differing in protonema morphology, shoot arrangement and leaf morphology. There was correlation between variation in the cultures and in the original field populations in some characters such as length of the leaf apiculus but other differences between the field populations, notably in stem length, leaf length and nerve excurrence, were not maintained in cultivation.     

Cation contents of acrocarpous and pleurocarpous mosses growing on a strontium-rich substratum

Abstract

A new species, Nanobryum thorsbornei, is described from northern Queensland, Australia, and compared with N. dummeri, an African species to which it seems most closely allied. They both have a remarkable persistent protonema which is partly pseudothallose but the leaves of the Australian species are trilobate, a feature lacking in the African species. The relationship of Nanabryum with Fissidens, particularly F. gladiolus, is discussed.