Proceedings of the Academy of Natural Sciences of Philadelphia Volume 20

9781130832976: Proceedings of the Academy of Natural Sciences of Philadelphia Volume 20

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1868 Excerpt: ... some of those of the last named genus, by the splittingaway of the outer parapet of the dentary bone. As no traces of alveoli have been thus rendered visible, I suspect the dentition to have been pleurodont, as in existing Batrachia. No external surface of the mandible remains, but there are no impressions of sculpture on the matrix. A little external face of the premaxillary displays none. Measurements. Lines. Preserved length of ramus (imperfect) 11. Depth at last tooth 2. Length of exposed tooth 1-7 " dentary 7-5 Depth at coronoid... 3-5 " at first tooth 1-3 SAUROPLEURA Cope. Neural and haemal elements of the caudal vertebrae elongate, distally dilated and grooved, attached by contracted bases. Ventral aspect defended by a series of oblique dermal ribs on each side, which meet anteriorly on the median line. Limbs distinctly developed. Ribs long, well developed. Scales none. No dermal bones have been discovered, nor are any portions of the cranium known. This genus is allied to the Urocordylus of Huxley, recently discovered in the coal measures in Leinster, Ireland. It differs only in the presence of elongate lizard-like ribs (whence the name), and in the absence of " oat-shaped scales" of the upper surfaces. It is a matter of much interest in American palaeontology that this remarkable type should be found to occur in our coal measures. It was first announced by Dr. Newberry at the meeting of the American Association for the advancement of Science for 1867 (see Proceedings, p. 144), as a supposed Urocordylus, occurring with Ophiderpeton. He mentioned at the same time the discovery of the ganoid Dinichthys Newb. A The forms discovered by Dr. Newberry have an interesting relation to those of Ireland, such as types of the present period...

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