. Fossil plants : for students of botany and geology . Paleobotany. 402 BENNETTITAIiES [CH. by thin-walled parenchyma. Some of the scales at the periphery of the receptacle where there are no seed-stalks are broader and may have six vascular bundles; this, Lignier suggested, might be regarded as evidence of the reduction of the interseminal scales from leaves possessing a terminal limb; but a further examination of scales at the periphery of the flower led him to the conclusion that the distal sweUing of the scales is solely due to the hypertrophy of conjunctive tissue and is not the result of
. Fossil plants : for students of botany and geology . Paleobotany. 402 BENNETTITAIiES [CH. by thin-walled parenchyma. Some of the scales at the periphery of the receptacle where there are no seed-stalks are broader and may have six vascular bundles; this, Lignier suggested, might be regarded as evidence of the reduction of the interseminal scales from leaves possessing a terminal limb; but a further examination of scales at the periphery of the flower led him to the conclusion that the distal sweUing of the scales is solely due to the hypertrophy of conjunctive tissue and is not the result of the modification of a reduced limb^ The morphological value of the interseminal scales and seed-stalks has not been definitely settled, though the probability is that they are homologous organs. Feo. 527. Cycadeoidea Jlorierei. Transverse section of interseniinal scales and. seeds near the apex of the latter; seeds 1 and 2 show the pollen-chamber, a; the fibrous layer, b, forming wings and extending across the fleshy tissue; c, the radial layer; seeds 3 and 4 are aborted. (After Lignier.) The letters a, b, c, in this figure correspond to cp. cf, and ar in figs. 525, 526. and fohar. Solms-Laubach^ suggested that both may be axial, the seed-stalks representing axes ending in a flower reduced to a single ovule; or, he adds, the seed-stalks may just as well be carpels, though in that case we should have the unusual pheno- menon of terminal seeds. The interseminal scales may be aborted seed-stalks crushed between the latter; or if the seed-stalks are axes, the scales may be fohar. He is inchned to see in the scales the bracts and prophyUs of seed-stalks to which must be added such bracteoles, preceding the seed or flower, as may happen to spring from the seed-stalks. Pearson', on the assumption that 1 Lignier (04). ' Solms-Laubach (91). ' Pearson (09).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - color
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