Anatomy of the Dicotyledons.
About: This article is published in American Midland Naturalist.The article was published on 1950-11-01. It has received 2511 citations till now.
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01 Oct 1969
TL;DR: The study of the cuticle in living and fossil gymnosperms has made it abundantly clear that stomatal and other epidermal characters are often of great value not only in the delimitation of genera but also in distinguishing the fragmentary fossil remains of allied species.
Abstract: The study of the cuticle in living and fossil gymnosperms has made it abundantly clear that stomatal and other epidermal characters are often of great value not only in the delimitation of genera but also in distinguishing the fragmentary fossil remains of allied species (see Florin 1931, 1933, 1958). In the early thirties of the present century, two comprehensive works appeared dealing with the systematic value of these characters in the living and fossil angiosperms. The first by Odell (1932) describes the cuticle in 84 genera of the living angiosperms and the conclusion is reached that none of the epidermal features of the vegetative parts of the living or fossil angiosperms is really satisfactory for diagnostic work. Contrary to this Edwards (1935) stated that the structural differences in the leaf epidermis do provide a means of distinguishing some closely related taxonomic groups. He, however, argued that as with other features in classification a sum total of the epidermal characters must be taken into account. Since the appearance of these two publications, a considerable body of data has accumulated regarding the cuticle. However, in the absence of any comprehensive account, it was thought worthwhile to bring together the available information on this aspect. I propose to complete it under two separate articles, the first one will deal with the monocotyledons and the second with the dicotyledons.
27 citations
Cites background from "Anatomy of the Dicotyledons."
...The first by Odell (1932) describes the cuticle in 84 genera of the living angiosperms and the conclusion is reached that none of the epidermal features of the vegetative parts of the living or fossil angiosperms is really satisfactory for diagnostic work....
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TL;DR: It is argued that positional changes in the initiation of organs is an evolutionary process that may have remarkable effects on plant construction.
27 citations
TL;DR: Wood ofTrimeniaceae may be regarded as highly mesomorphic, corresponding to the moist habitats in which all of the species occur, and similarity to some other lauralean (annonalean) families may be found: in mucilage presence, Trimeni Families resemble Lauraceae rather thanMonimiaceae.
Abstract: Four collections of three species ofTrimenia and one collection ofPiptocalyx were studied; early-formed and later-formed wood was analyzed for oneTrimenia. Liquid-preserved material permitted analysis of mucilage and starch storage in wood ofT. neocaledonica andP. moorei. BecausePiptocalyx is scandent whereasTrimenia is arborescent, wood differences relative to evolution of a climbing habit could be examined.Piptocalyx contrasts withTrimenia in having wider vessels, more numerous per mm2, resulting in a conductive area five times greater per unit area than that of theTrimenia woods averaged.Piptocalyx has appreciably fewer bars per perforation plate and thus much greater conductive area per perforation plate than have the species ofTrimenia. Rays inPiptocalyx are much taller and wider than those ofTrimenia. Wood ofTrimeniaceae is highly primitive in its scalariform perforation plates, scalariform lateral wall pitting on vessels, relatively long vessels elements, and heterocellular rays. Imperforate tracheary elements are septate nucleate fibertracheids (or even libriform fibers) rather than tracheids, but loss of borders on pits (and thus lowered conductive function of the imperforate tracheary elements) can be explained by the development of these elements into starchstoring cells. Some fiber-tracheids inT. neocaledonica are enlarged mucilagecontaining cells. Details of vessel structure inTrimeniaceae are similar to those ofMonimiaceae (s. s.), but similarity to some other lauralean (annonalean) families may be found: in mucilage presence,Trimeniaceae resembleLauraceae rather thanMonimiaceae. Wood ofTrimeniaceae may be regarded as highly mesomorphic, corresponding to the moist habitats in which all of the species occur.
27 citations
TL;DR: A histochemical technique for calcium oxalate localization was applied to the cleared leaves to complement the physical identifications of the crystals and represents a simple method for in situ identification of calcium Oxalate.
Abstract: Crystals from species of Rhynchosia, Phaseolus, Canavalia, and Begonia were observed in cleared leaves and their specific locations were noted. Crystals were isolated from leaves, purified, verifie...
27 citations
Journal Article•
TL;DR: The variation in morphology and distribution of foliar trichomes emerged as an important supportive taxonomic tool in delimiting species of genus Hibiscus.
Abstract: Qualitative and quantitative micromorphological characters, distribution and systematic relevance of both glandular and eglandular foliar trichomes in species of genus Hibiscus (Malvaceae) including H. caesius, H. mutabilis, H. rosa-sinensis, H. sabdariffa, H. schizopetalus, H. syriacus and H. trionum were characterized. Diversity of these epidermal appendages were separated into eight main types. Glandular capitate trichomes were the most abundant on both leaf surfaces of all the examined taxa. H. mutabilis was discrete in having multicellular uniseriate columna as a prominent feature of its abaxial leaf surface, whereas H. schizopetalus and H. sabdariffa could be demarked due to the twisted or Spirogyra-like appearance of their eglandular trichomes. In summary, the variation in morphology and distribution of foliar trichomes emerged as an important supportive taxonomic tool in delimiting species of genus Hibiscus.
27 citations