摘要:

AbstractFlask-shaped gemmae of BritishLeptodontium flexifolium(With.) Hampe are discussed in the context of previously described ellipsoidal and oboyoid gemmae and point to the need for taxonomic reappraisal of the two closely related species,L. flexifoliumandL. styriacum(Jur.) Limpr.. Scabrous leaves in the former are associated with mamillae rather than papillae.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.737

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractColourless, usually unicellular, tubers occur on the rhizoids ofDiscelium nudum.They are evidently not the rhizoid gemmae previously claimed to occur in this species, which were multicellular.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.741

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractContrary to an earlier report that the spore sac inArchidiumis endothecial in origin, evidence is presented from this earlier report onA. alternifoliumand from observations onA. stellatumthat the spore sac is amphithecial in origin as in the Bryideae. The retention ofArchidiumin the Archidiidae is supported on sporophytic evidence.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.745

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractThe development of alar cells inDrepanocladus aduncusandD. exannulatusfollows quite different paths. The type of development found inD. aduncusis also found inD. sendtneri, D. capillifoliusand, in a somewhat modified form, inD. uncinatus, D. lycopodioides, D. brevifolius, Scorpidium turgescensandCalliergon trifarium.TheDrepanocladus exannulatustype was found in the N. EuropeanCalliergonspecies (exceptC. trifarium), inDrepanocladus tundrae, D. fluitans(incl.D. h-schulzei),D. exannulatusvar.procerus, D. trichophyllusandD. badius.Outside theCalliergon-Scorpidium-Drepanocladus-complex of species types of development like that inDrepanocladus aduncusseem to be the most frequent though other quite different kinds do occur.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.753

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractThe sporeling development inFrullania tamarisici(L.) Dum. ssp.tamarisciis described for the first time. Its pattern belongs to theFrullania-typein 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.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.761

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractThe effects of a 24 h dehydration period on plastid ultrastructure and their starch content have been studied on the leafy gametophyte of a poikilohydrous mossPolytrichum formosumHedw. It has been shown that desiccation induces a swift resorption of the starch grains in the plastids of the meristematic cells of the shoot apex without any major disorganisation of the thylakoids. However starch grains are preserved in the dehydrated tissues of the adult leaves. The starch hydrolysis is continued with a marked increase of the sucrose concentration to this may be attributed an osmoregulatory role in the first stages of the water loss. Upon rehydration the plastid ultrastructure is entirely restored with new starch inclusions appearing in less than 4 h.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.765

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractBranching inFontinalisoccurs primarily in the range of 5 to 15°C and differs among the species. Pool conditions reduce branching significantly among most species and can account for the reduction in growth observed in those conditions.Data on six species ofFontinalissupport the hypothesis thatFontinalisproduces more rhizoids in response to temperatures above 10°C and that this production will correspond with the summer season in the north temperate and arctic zones. Since branch production is not inhibited at 15°C and is only slightly reduced at 20°C, it appears that rhizoid production does not interfere significantly with branch production. Since rhizoid clumps often originate at branch innovations, the continuation of branching throughout the summer could aid the moss in attaching during the summer when its chances of success are maximum.

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.779

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.791

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.792

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0373-6687    

DOI:10.1179/jbr.1987.14.4.793

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor