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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TL;DR: Angiosperm woods from the Campanian Crevasse Canyon Formation and the Maastrichtian Jose Creek Member of the McRae Formation are described, with Baasia and Fulleroxylon representing the first North American fossil wood records of Celastraceae and Myrtaceae, respectively.
Abstract: Late Cretaceous angiosperm woods from the Western Interior of North America are poorly known relative to palynomorphs and leaf macrofossils. In this report we describe angiosperm woods from the Campanian Crevasse Canyon Formation and the Maastrichtian Jose Creek Member of the McRae Formation, in south-central New Mexico. New taxa include Baasia armendarisense (Celastraceae), Fulleroxylon armendarisense (Myrtaceae), and Pygmaeoxylon paucipora (magnoliid of uncertain affinities). Previously described taxa include Metcalfeoxylon (eudicots), Paraphyllanthoxylon (most likely Laurales), and Platanoxylon (Platanaceae). Tree habit is indicated for Metcalfeoxylon, which is known from in situ stumps with a maximum basal diameter of 0.75 m, and for Baasia and Paraphyllanthoxyon, which are known from axes at least 0.14 m in diameter. Baasia and Fulleroxylon represent the first North American fossil wood records of Celastraceae and Myrtaceae, respectively. Baasia also indicates that within Celastraceae, the pattern of...
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Cites methods from "Anatomy of the Dicotyledons."
...Affinities were determined by consulting the literature (Metcalfe and Chalk 1950; Détienne and Jacquet 1983; Ilic 1987, 1991) and searching the online database InsideWood (InsideWood 2004–onward; Wheeler 2011)....
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TL;DR: Detailed studies of the leaf include features such as marginal and laminar hydathodes, «warts», hair types, and groups of 2–5 palisade-like cells connected to each other by short communicating tubes.
25 citations
25 citations
TL;DR: The standard IAWA List of wood anatomical characters are discussed, which are defined primarily for identification, and recast them in a format that is more appropriate for cladistic analysis.
Abstract: Wood anatomy is an important source of systematically informative character information that can and should be used in cladistic phylogenetic analyses of relationships in flowering plants. However, the results of a cladistic analysis are only as good as the characters and observations, which together comprise the data set that is analyzed. The goal of this paper is to address the former of these issues, specifically the definition and use of wood anatomical characters in cladistic analyses. We first provide a brief introduction to the principles of cladistics. We then discuss the standard IAWA List of wood anatomical characters, which are defined primarily for identification, and recast them in a format that is more appropriate for cladistic analysis. As a means of illustrating some common problems and their possible solutions, we conclude with a brief discussion of recent cladistic analyses that have included wood anatomical characters.
25 citations
TL;DR: The Onagraceae is unique among families of comparable size in the heterogeneity of stigma form and physiology, and all species of the dry-stigma genera in the family are self-compatible, but not all are inbreeding because of the existence of other mechanisms enforcing outcrossing.
Abstract: The Onagraceae is unique among families of comparable size in the heterogeneity of stigma form and physiology. Studies of the receptive surfaces of stigmas from representatives of all genera of the family have shown that a range of types exists from papillate to non-papillate, and from “wet”, bearing a free-running secretion, to “dry”, lacking such a secretion, most genera falling in the former category. Self-incompatibility is wholly restricted to wet-stigma species, and direct and circumstantial evidence indicates that it is always likely to be of the gametophytic type, as in certain Oenothera species that have been the subjects of detailed genetical and physiological research. Whilst Oenothera and most other self-incompatible species in the family appear to reject incompatible pollen mainly in the stigma surface layers, the precise site is subject to both genetical and environmentally-determined variation. Intraspecific polymorphy in sex function is known in the genus Fuchsia, most species of which have wet stigmas. Female sterility in the functionally male flowers of certain species of this genus appears simply to be due to a failure to produce adequate stigma secretion. All species of the dry-stigma genera in the family are self-compatible, but not all are inbreeding because of the existence of other mechanisms enforcing outcrossing. The stigmas of some possess certain unique features, apparently related to water conservation. Possible evolutionary trends in the family and in the breeding and pollination systems are briefly discussed in the light of what is now known of pollen-stigma relationships.
25 citations