. The "Fern ledges", Carboniferous flora of St. John, New Brunswick [microform]. Geology, Stratigraphic; Paléontologie; Paléobotanique; Paleobotany; Paleontology; Géologie stratigraphique. 90 have been exhaustively studied by many palaeobotanists, it would require a better basis for its establishment than U afforded by the one graphitised and incomplete specimen from St. John. The small cup like hollow formed at the apex of the wing IS sometimes closed or nearly closed over the top by the claw hke tips of the wing, in others it is open like a small bowl. Examples of different apic
. The "Fern ledges", Carboniferous flora of St. John, New Brunswick [microform]. Geology, Stratigraphic; Paléontologie; Paléobotanique; Paleobotany; Paleontology; Géologie stratigraphique. 90 have been exhaustively studied by many palaeobotanists, it would require a better basis for its establishment than U afforded by the one graphitised and incomplete specimen from St. John. The small cup like hollow formed at the apex of the wing IS sometimes closed or nearly closed over the top by the claw hke tips of the wing, in others it is open like a small bowl. Examples of different apices of the seeds are shown in text fig. 19, Md can also be recognised in the photographs of pis. XXI, AJLll and "â¢â iii. 2SSiXCc^"ii!""' â ^"°"- ^'^ " â¢^- '^'"^ t^ ind«,UUon of th. Dawson (1871, p. 61) concluded that the structure of these seeds ^as similar to that of Taxus and the "woody tegmen (was] surrounded by a fleshy outer coat, and that the notch at the apex represents the foramen or micropyte of the ; Though at first sight this seems an attractive view, and the resemblance between this seed and the diagrams published of gymnospermic seeds with poller, chambers is considerable; it must be remembered that these diagrams are made from longitudinal sections and that in the St. John specimens we are deaUng with the entire seeds flattened out, vhich consequently could not show its poUen chamber in this diagrammatic way, for it would be covered by the outer layers flattened over it. The fact that the cup shaped hoUow in the top of the St. John specimens is not veUed or covered by any film of a membrane shows that it was not a three^imensional pollen chamber, but a simple notch in a flat wmg. The seeds doubtless had pollen chambers, and micropyles leading to them, but they were in the apex of the. Please note that these images are extracted from scanned page images that may have been digitally e
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Keywords: ., bookcentury1900, bookdecade1910, booksub, booksubjectpaleontology
