61 research outputs found
A provisional determination key to 54 continental Africal dichapetaluns species, based on anatomical characters of the secondary xylen
Get PDFTentative determination key to 600 trees, shrubs and climbers from the Ivory Coast, Africa, mainly based on characters of the living bark, besides the rhytidome and the leaf
Get PDFHistological investigations of the secondary phloem of gymnosperms
Get PDFAn anatomical study of secondary phloem of the different species of Gymnosperms showed that three categories could be distinguished, which may represent three evolutionary stages. These three categories were:Pseudotsuga taxifolia type, to which belong many Pinaceae (while the other Pinaceae species belong to a subtype, e.g. the Tsuga canadensis subtype);Gingko biloba type, to which belong the Cycadaceae, Araucariaceae and many Podocarpaceae and Taxaceae;Chamaecyparis pisifera type, to which belong the Cupressaceae, Taxodiaceae and the rest of the Taxaceae and Podocarpaceae.The phylogenetic sequence of the axial system and the reduction of the phloem rays starts in the Ps. taxifolia type with an almost uniform axial system and ray- albuminous cells, and a complex heterogeneous phloem ray, differentiating through the G. biloba type to the C. pisifera type, which has a highly specialized axial system with phloem-albuminous cells and a simpler, reduced homogeneous phloem ray. The reduction of the phloem rays parallels the differentiation of the axial system
Determination keys for important West - European woods and tropical commercial timbers : with the help of a hand-lens or a light microscope
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Histological investigations of the secondary phloem of gymnosperms
No full textAn anatomical study of secondary phloem of the different species of Gymnosperms showed that three categories could be distinguished, which may represent three evolutionary stages. These three categories were:Pseudotsuga taxifolia type, to which belong many Pinaceae (while the other Pinaceae species belong to a subtype, e.g. the Tsuga canadensis subtype);Gingko biloba type, to which belong the Cycadaceae, Araucariaceae and many Podocarpaceae and Taxaceae;Chamaecyparis pisifera type, to which belong the Cupressaceae, Taxodiaceae and the rest of the Taxaceae and Podocarpaceae.The phylogenetic sequence of the axial system and the reduction of the phloem rays starts in the Ps. taxifolia type with an almost uniform axial system and ray- albuminous cells, and a complex heterogeneous phloem ray, differentiating through the G. biloba type to the C. pisifera type, which has a highly specialized axial system with phloem-albuminous cells and a simpler, reduced homogeneous phloem ray. The reduction of the phloem rays parallels the differentiation of the axial system
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