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: Wood of Ascarina is highly mesomorphic, with age of plant, vessels increase in diameter, vessel elements and fiber-tracheids increase in length, and rays become wider and have a higher proportion of procumbent cells; uniseriate rays decrease in abundance.
Abstract: Quantitative and qualitative features are presented for 13 collections of 8 species of Ascarina. Wood anatomy is maximally primitive in most respects; moderate exception occurs in the imperforate tracheary elements, which range from tracheidlike (A. solmsiana) to fiber-trachei ds (septate in two species). Perforation plates are scalariform, average more than 100 bars per plate, and have bordered bars. Even more significantly, portions of the primary walls in perforations characteristically fail to dissolve; these pit membrane portions range from nearly intact (much like the pit membranes in pits on end walls of tracheids of vesselless dicotyledons) to remnant strands or flakes. Dissolution of pit membranes in perforations is apparently inhibited by deposition of resinlike substances in some species; the rugose surfaces formed by these deposits may account for a report of vesturing on vessel walls of Ascarina. Axial parenchyma is diffuse, with only very small expressions of diversification; apotracheal banded parenchyma is, however, present in A. swamyana. Wood of Ascarina is highly mesomorphic. With age of plant, vessels increase in diameter, vessel elements and fiber-tracheids increase in length, and rays become wider and have a higher proportion of procumbent cells; uniseriate rays decrease in abundance. The implications of wood anatomy data on generic distinctions within the family and on the systematic position of Chloranthaceae will be examined when monographs on woods of the other genera have been completed.
29 citations
Cites background from "Anatomy of the Dicotyledons."
...The primitive nature of wood ofChloranthaceae has been noted by such authors as Swamy and Bailey ( 1950) and Metcalfe ( 1987) prior to discovery of this feature....
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...Phylogeny and Systematic Relationships The wood of Chloranthaceae is proclaimed to be unspecialized by Metcalfe (1987)....
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...Metcalfe (1987) does not mention vasicentric parenchyma as present in Ascarina....
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TL;DR: A preliminary cladistic analysis was undertaken to evaluate the relationships between families of the superorder Lamiiflorae sensu Dahlgren, and several family interrelationships could not be resolved, although several groups were common to all three cladograms.
29 citations
TL;DR: The long separate history of Brunonia may be the result of its early entry into the arid areas, possibly before other goodeniads, with secondary invasions of the higher rainfall zones only much later.
Abstract: Although Brunonia has had a long separate history from the other Goodeniaceae, they do appear to be related, and it remains a matter of personal preference whether one places it in a subfamily of Goodeniaceae or in a separate family. Since I prefer large families to give easily recognizable groups, I opt for the first alternative. The long separate history of Brunonia may be the result of its early entry into the arid areas, possibly before other goodeniads, with secondary invasions of the higher rainfall zones only much later. The relationship between Goodeniaceae and Campanulaceae is not very close, and it seems they must both have arisen quite early in the evolution of the Metachlamydeae. The evolution of the Goodeniaceae as a whole and the Campanulaceae occurred after the break up of Gondwanaland, in the temperate areas of each continent. The Stylidiaceae are primitively a cool to cold montane group of southern Gondwanaland.
29 citations
TL;DR: Structural diversity and developmental patterns in the Ghanaian Saxicolella species are compared with other African Podostemoideae and taxonomically used characters such as root, holdfasts, pollen, capsules, and seeds are demonstrated and discussed.
29 citations
Journal Article•
TL;DR: Diversity in stomatal type, midrib and petiole vascularisation, sclerenchyma support, foliar sclereids, mucilage cells, secretory cavities, and cristarque cells provide evidence in favour of a separate family status of the members of the Linaceae complex.
Abstract: The leaf anatomy of the Linaceae complex (Linaceae s.s., Hugoniaceae, Ixonanthaceae, Humiriaceae and Erythroxylaceae) and putative allies ( Ctenolophon, Lepidobotrys, Irvingiaceae) is surveyed, mostly on the basis of original observations (72 specimens, 27 genera), partly from data in the literature.
Diversity in stomatal type, midrib and petiole vascularisation, sclerenchyma support, foliar sclereids, mucilage cells, secretory cavities, and cristarque cells provide evidence in favour of a separate family status of the members of the Linaceae complex. Allantospermum and Cyrillopsis are best accommodated in the Ixonanthaceae. Irvingiaceae (often treated in or near Simaroubaceae) show similarities with the Linaceae complex, albeit more closely to the Hugoniaceae than to the Ixonanthaceae to which they have been transferred by some authors. Ctenolophon seems unrelated, but leaf anatomy gives no strong clues for its true affinities. Lepidobotrys may be related to the Linaceae complex, but its leaf anatomy is also in good agreement with treatment in or near the Oxalidaceae. Within the Ixonanthaceae, Phyllocosmus deserves generic status next to Ochthocosmus on account of the exclusive occurrence of tracheoidal idioblasts in the latter and lack thereof in the former. The results are discussed in connection with evidence from other sources of enquiry.
29 citations