Proceedings of the American Philosophical Society, Vol. 47

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Excerpt from Proceedings of the American Philosophical Society, Vol. 47: Held at Philadelphia for Promoting Useful Knowledge Four years ago, to the small but very peculiar and ancient group of shark-like fishes known as Chimeroids, Holocephala and Chis mopnea, Garman added a Japanese species, Rhinochimaera pacified. His description of the brain was brief and the figures represented only the general form from the dorsum, venter and side. A well preserved example recently obtained from Alan Owston of Yoko hama enables me to confirm Carman's account as to the general Chimeroid character of the brain, especially the cerebellum and adjoining segments, and as to the extraordinary - probably unique slenderness of the other regions, due not merely, as in Chimaera, to the elongation of the cerebral crura, but also to the pedunculate condition of the olfactory bulbs, whose tracts or crura equal the cerebral in length. The partial dissection of this brain discloses additional features, as shown upon the colored crayon diagram, viz., (1) The cerebral and olfactory cavities. (2) The complete circum scription of these cavities by walls of moderate thickness at the olfac tory bulbs and parts of the cerebral hemispheres, but mostly thin and largely membranous. (3) The olfactory crura have thinner walls than in any brain known to me, and the proper nervous sub stance seems to be confined to their outer or lateral sides. (4) The roof of the undivided cerebral cavity is wholly membranous, like wise a narrow mesal zone of the ¿oor, but the ¿oors of the hemi spheres are connected by a terma lamina terminalis as described by me in C himaera in 1877. (5) Each substantial wall of the cere bral cavity begins as a single broad band which divides into a ventral and a lateral portion as it approaches the hemisphere, this condition has not been observed by me in any. Other brain. (6) There was found no trace of the N ervas terminalis of Locy, nor has it been recognized in any other member of the group. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.