摘要:

An account of the pollen morphology found in the generaDysoxylumandPseudocarapa(Meliaceae) is presented. Pollen grains are illustrated by means of electron and some light micrographs. The majority of taxa release grains as tetra‐colporate monads. Tetrads have previously only been known inPseudocarapa.They are also recorded here in three species ofDysoxylum.The taxonomic implications of this are discussed andPseudocarapais reduced to a synonym ofDysoxylu

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00418.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

The effectiveness of geographical isolation, ecological isolation, temporal isolation, mechanical isolation, ethological isolation, cross‐incompatibility, hybrid inviability, hybrid sterility and hybrid breakdown as practical barriers to gene flow in the field betweenConospermum taxifolium, C. ericifolium, C. ellipticumandC. longifoliumhas been quantified. The barriers to gene flow betweenC. ericifoliumandC. ellipticumare completely effective, owing to their allopatric distributions. The barriers to gene flow betweenC. taxifoliumand these two species are only partially effective, as their ecological separation breaks down in intermediate habitats, and partially‐fertile F1plants can grow in the areas of overlap. The barriers to gene flow betweenC. longifoliumand the other three species are almost completely effective, as cross‐incompatibility is very high and the F1plants are female‐

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00419.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Some taxonomic characters may escape observation when only a small part of the vegetative body of the plant is examined. For this reason, these characters are likely to be overlooked. Phyllotaxy varies in most cases from the trunk to branches. Serial buds, when they exist, may be lacking in the axil of some leaves. Syllepsis is easier to see on the trunk than on twigs. Architectural models are established after appropriate observation of the whole plant or, better, with different individuals of the same species. Nevertheless, many of these characters can be readily observed and frequently help to identify a woody plant without its flowers or fruits. Some interpretations concerning systematics and evolutionary biology are also given.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00420.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Membranous ligules of 49 grass species, representing ten tribes, were anatomically studied using light, fluorescence and transmission electron microscopy. Great variety in ligule abaxial surface anatomy was found but internally all ligules so studied possess a tripartite structure of two uniseriate epidermes enclosing a mesophyll tissue of varying thickness. Chloroplasts were present in most of the ligules (where this feature was determined) supporting the view that this is a photosynthetic leaf organ. Of the 36 species examined by fluorescence microscopy eight showed evidence of having a gland‐like adaxial epidermis with numerous mitochondria, dictyosomes, strands of rough endoplasmic reticulum and fibrillar material within the periplasmic space next to the outer tangential wall. Existing hypotheses of ligule function are discussed in the light of these anatomical results, and a new hypothesis is propose

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00421.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

An account of the Myxomycetes of the Kimberley Region of north Western Australia is presented. It is based on collections obtained mainly from the Napier and Oscar Ranges during the Kimberley Research Project, 1988. The thirty‐two collections represent eighteen species, four of which are new records for Australia and twelve new to Western Australia. All but one are new to the Kimberley region, from where only four species were previously know

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00422.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

It has been suggested by some authors that the low fruit to flower ratio in some Proteaceae is due to andromonoecy, while others, looking particularly atBanksia, have not been able to find evidence for male flowers in the inflorescences.Stirlingia latifolia, Xylomelum occidentalsandX. angustifoliumare clearly andromonoecous, while no evidence for this condition could be found inBrabejum stellatifoliutn.Production of fertile fruit is related to andromonoecy inXylomelumandS. latifoliabut not inBrabejum.It is unlikely that all‐encompassing solutions will be found to what initially seem to be widespread traits in the family, especially in regard to pollination biology, as the genera in the family occupy widely different environments and have very diverse ecological range

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00423.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1994.tb00418a.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY