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Show 188 MR. F. E. BEDDARD ON THE [Mar. 6, The animal when dead weighed 5 lb. 9 oz., there being no undue distention of the stomach and alimentary canal with food. The weight of the fresh brain was 4 oz. It was preserved first of all in weak spirit (about 45 per cent.), and then, after 24 hours and removal of the pia mater, transferred to strong spirit. With this treatment the brain seems to have altered very little from the conditions observable in life. There is no suggestion in the appearance and direction of the sulci of any changes. I was therefore very much surprised to see the relations of the cerebellum to the cerebrum, which are apparent in the accompanying drawing (fig. 1). The cerebrum not only completely covers the cerebellum, but extends for some way beyond it. With even a liberal discount for contraction (of which, however, I do not see the need), it is difficult to understand the brain-cast-of the accuracy of which there can be no question-prepared by Sir W . Flower, save on the hypothesis of an abnormality l. Fig. 1. Brain of Siamang. Inner view of left hemisphere. M.P.O., mesial parieto-occipital fissure; CA., calearine : OPT., optic nerve; O L „ olfactory. The Sylvian fissure seems to call for no particular remark. The anteriorly directed fronto-orbital'fissure is well developed, and the exposed island of Reil is extremely conspicuous. This is, however, by no means a peculiarity of Hylobates syndactylus as compared with other Gibbons. The parieto-occipital fissure.-I take it that the fissure lettered P.O. represents the parieto-occipital fissure of other Apes plus the Simian fissure. It will be observed that on both sides of the brain the Simian fissure, instead of terminating without reaching the mesial surface of the brain, as is often the case with Anthropoid Apes, bends forward and joins the parieto-occipital (fig. 2, p. 189). 1 Dr. Keith has pointed out to me that the overlapping of the cerebellum by the centrum is a characteristic of youth, and that the brain-cast studied by Sir W . Flower was therefore that of an old animal. |