. Fossil plants : for students of botany and geology . Paleobotany. XXXV] PACHYTBSTA 326 interlocking of nucellus and canopy in Lagenostoma, as also with the ruminated endosperm of Torreya. We have no definite information as to the plants which bore Pachytesta, but it is probable that they were members of the MeduUoseae. Grand'Euryi beheves Pachytesta to be the seed of Alethopteris Grandini, though this view requires confirmation. This author figures several Pachytesta seeds attached in two obhque rows to a comparatively slender axis which may be the rachis of. Fig. 497. Pachytesta. Transverse
. Fossil plants : for students of botany and geology . Paleobotany. XXXV] PACHYTBSTA 326 interlocking of nucellus and canopy in Lagenostoma, as also with the ruminated endosperm of Torreya. We have no definite information as to the plants which bore Pachytesta, but it is probable that they were members of the MeduUoseae. Grand'Euryi beheves Pachytesta to be the seed of Alethopteris Grandini, though this view requires confirmation. This author figures several Pachytesta seeds attached in two obhque rows to a comparatively slender axis which may be the rachis of. Fig. 497. Pachytesta. Transverse section of a seed showing the exotesta, ex, with sclerous layers and vascular strands (black), the endotesta (dotted), the nucellus with its ring of vascular bundles, n, and the prothaUus, p. The three radial plates in the exotesta are seen at a, b, c, with the trabeculae, t, and internal to these are the grooves in the endotesta engaging with ribs on the nucellus, nr. (After OUver.) a large compound frond^. Eenault and Zeiller^ have figured specimens of P gigantea and P. incrassata from Commentry which afford a good idea of the form of these large seeds; the genus is recorded also from Gard, Blanzy*, and other locahties. Kidston^ described a large oval seed, blunt at each end, from the Middle Coal Measures of Lancashire as Carpolithus Wildii which he thinks may be alHed to Pachytesta, but adds, 'I do not think we are justified in placing mere impressions of plants in genera, 1 Grand'Eury (04). 2 Grand'Eury (90) A. PL vm. fig. 3; (77) A. PI. xvi. fig. 5. » Eenault and ZeiUer (88) A. PI. 73. * Zeiller (06) B. p. 229. " Kidston (92) p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Seward, A. C. (Albert Charles), 1863-1941. Cambridge : University Press
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
