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: Eocene Ginkgoites patagonica was present in plant communities, and it is the last representative of a still poorly understood southern ginkgophyte lineage that was distinct from the ancestors of G. biloba of the Northern Hemisphere.
Abstract: Premise of research. The ginkgophytes are an ancient group of gymnosperms with a long history starting during the late Paleozoic and reaching the present with the unique species Ginkgo biloba L. In order to better characterize the early and middle Eocene (ca. 52.2 and 47.7 Ma) leaf species Ginkgo patagonica Berry from northwest Patagonia, Argentina, new specimens were studied, focusing on their morphological and anatomical characters.Methodology. The specimens were studied with LM, epifluorescence, SEM, and TEM.Pivotal results. The diagnosis of the species Ginkgoites patagonica comb. nov. is enlarged to include anatomical and ultrastructural epidermal characters. Herein, the species Ginkgo patagonica is shown to have characteristics that clearly separate it from the genus Ginkgo L., and it is therefore recombined to the genus Ginkgoites Seward.Conclusions. Eocene Ginkgoites patagonica was present in plant communities, and it is the last representative of a still poorly understood southern ginkgophyte line...
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Cites methods from "Anatomy of the Dicotyledons."
...The terminology of Metcalfe and Chalk (1979) was used for stomata classification; Holloway (1982) and Lyshede (1978, 1982) were used for ultrastructural descriptions....
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TL;DR: This study describes for the first time the origin, development, and secretion process of the glands that occur in the aerial organs of Chamaecrista dentata and highlights their importance on the adaptive success of this species.
Abstract: Premise of research. Despite the taxonomic and phylogenetic importance of secretory structures in Caesalpinioideae, especially in Chamaecrista species, the characterization of their external glands is scarce and fragmented. The structural features of these glands during the course of development and the histochemistry of the secretion products were studied to elucidate their anatomy, ontogeny, and secretion process, as well as to infer their functional role.Methodology. Samples of leaves and flowers were fixed and prepared following standard methods for scanning electron microscopy or embedding in resin for anatomy. Histochemical tests were carried out on fresh sections to detect the main classes of compounds present in the secretion.Pivotal results. The glands must be classified as trichomes since they originate from a single protodermal cell. They consist of a very short stalk and a large, multicellular spherical or oblong-shaped glandular head with a long, beak-shaped filiform projection. At the tricho...
15 citations
Cites background from "Anatomy of the Dicotyledons."
...Although Metcalfe and Chalk (1950) have described the external glands of Chamaecrista as shaggy trichomes with a glandular spherical base, in the light of this study the region actually corresponds to the complex multicellular head of this exceptional type of trichome....
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TL;DR: In this article, a diagnosis of the genus Platanoxylon introduced by Andreanszky (1951) is given at first time, based on the wood features of the living members of Platanus L. The anatomical features of fossil plane woods are discussed in detail, and all fossil woods considered to be of Platanos-origin at any time are critically reviewed.
Abstract: Fur die Gattung Platanoxylon Andreanszky (1951) wird erstmalig eine Diagnose aufgestellt. Diese stutzt sich im allgemeinen auf die Holzmerkmale der heutigen Vertreter von Platanus L. Die platanenahnlichen, jedoch durch einige auffallige Merkmale von Platanoxylon abweichende Holzer, werden ausgesondert; ihre nahere Bearbeitung ist vorgesehen. Nach vorliegendem Material werden neun Arten von Platanoxylon teils erstmals, teils auf Grund einer Nachuntersuchung alteren Materials neu beschrieben. Davon besitzen 5 Arten Stammholzstruktur und vier Arten Wurzelholzstruktur. Die Funde stammen aus der VR Ungarn bzw. der USA und sind meistens miozanen Alters. Nach einer zusammenfassenden Diskussion uber die holzanatomischen Eigenschaften der fossilen Platanen wird eine kritische Ubersicht uber alle bisher bekannten, den Platanaceen zugeordneten Holzfossilen gegeben.
A diagnosis of the genus Platanoxylon introduced by Andreanszky (1951) is given at first time. In general, it is based on the wood features of the living members of Platanus L. The plane-like fossil woods distinguished from Platanoxylon by some important features are separated; their particular treatment is looked out. Based on present materials nine species of Platanoxylon are described in detail, partly at first time, partly by new investigation of specimens yet formerly treated. Here of 5 species show the structure of plane stem wood, 4 species such of plane root wood. The fossils investigated are deriving from Hungaria and the United States respectively and are mostly of miocene age. The anatomical features of fossil plane woods are discussed in detail, and all fossil woods considered to be of Platanus-origin at any time are critically reviewed.
15 citations
TL;DR: It is shown that morphological and epidermal characters of polymorphic leaves of typical platanoid appearance were formed in the Late Albian and remained essentially invariable to the present time, indicating the morphological stasis of these leaves combined with a wide variation range.
Abstract: The data on fossil platanoids and hamamelids are generalized, their morphological diversity and probable patterns of the establishment of the extant families Platanaceae and Hamamelidaceae are analyzed. It is shown that morphological and epidermal characters of polymorphic leaves of typical platanoid appearance were formed in the Late Albian and remained essentially invariable to the present time, indicating the morphological stasis of these leaves combined with a wide variation range. In view of association with essentially different reproductive structures, it is proposed to classify these leaves by the morphological system irrespective of the natural system of angiosperms. A new system of extinct platanoids and hamamelids, which is based on reproductive structures and includes two orders, Hamamelidales and Sarbaicarpales ordo. nov., is proposed. Hamamelidales comprises two extant families, Platanaceae (with the subfamilies Platanoideae subfam. nov. and Gynoplatananthoideae subfam. nov.) and Hamamelidaceae, and the extinct family Bogutchanthaceae fam. nov.; the new extinct order Sarbaicarpales ordo. nov. consists of two new families, Sarbaicarpaceae fam. nov. and Kasicarpaceae fam. nov. In a system of flowering plants that is based on molecular data, the families Platanaceae and Hamamelidaceae are assigned to remote orders, excluding close relationship (APG, 2003). At the same time, the system of APG II often contradicts morphological and paleontological data, while traditional ideas of morphologists concerning the common origin of these families have recently been supported by paleobotanic evidence. Probable origin of the families Platanaceae and Hamamelidaceae from a common polymorphic ancestral group is discussed.
15 citations
TL;DR: The objective was to evaluate the histochemistry of the leaf blade of Byrsonima verbascifolia, a species that has been reported as producers of secondary metabolites for pharmacological use, to find leaf regions which produced chemical compounds.
Abstract: Chemical components act in plant defense and protection, but many of them are extracted and used medicinally. For Cerrado, active chemical components are used in the treatment of diseases, which strengthens the necessity for pharmacological studies of plants of that environment. The objective was to evaluate the histochemistry of the leaf blade of Byrsonima verbascifolia (L.) DC., Malpighiaceae, Campomanesia adamantium (Cambess.) O.Berg, Myrtaceae, Roupala montana Aubl., Proteaceae, and Solanum lycocarpum A. St.-Hil., Solanaceae, species that have been reported as producers of secondary metabolites for pharmacological use. The 3rd node leaves (median, intercostal and margin regions) were collected, fixed, included in Paraplast® or 2-hydroxyethyl methacrylate, sectioned in microtome, stained and photographed on microscope. This analysis aimed to find leaf regions which produced chemical compounds. For histochemical tests, intercostal areas were selected from median region leaf of the 3rd node. Samples fresh and newly collected and fixed and embedded in Paraplast® were used. Tests were conducted for lipids, terpenoids, phenolic compounds, alkaloids, sugars and proteins. Alkaloids were observed only in R. montana, as well as the results for phenolic compounds. Flavonoids are present in B. verbascifolia and R. montana. The lipid composition was showed for the chemical compounds of B. verbascifolia and C. adamantium, which proved to be part of the essential oils or resins oils in C. adamantium idioblasts. The chemical compounds of B. verbascifolia, C. adamantium and R. montana are present mainly in idioblasts among the parenchyma and epidermal cells. C. adamantium has secretory cavities, but only with lipid content. The identification of chemical compounds has not been possible in mature leaves of S. lycocarpum.
15 citations