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Show 312 MR. F. E. BEDDARD ON THE [Mar. 28, and African Elephants. The internal lateral, superficial, and external lateral aspects are figured. I shall now proceed to describe the brain examined by myself. DESCRIPTION OF THE BRAIN. The outlines of the hemispheres (Plate XXII.) are not by any means exactly as have been depicted by Krueg; the comparatively narrow anterior half is, in m y specimen, barely so long as the broader posterior section; the lengths in m y specimen were (rather roughly) 41 and 3 inches respectively. It seems likely, therefore, that the general form of the hemispheres in this Elephant may now be fixed with something like certainty, and that the differences between the outlines of the brain in the Indian and African Elephants as portrayed in Krueg's sketches are not real differences, so far at any rate as concerns the proportions referred to above. I did not find that tbe rhinal fissure had so long a visible course upon the lateral aspect of the brain as it is depicted by Krueg ; this gives to the brain an altogether peculiar appearance in these drawings, which do not seem to be a correct expression of the facts as seen in the brain examined by myself. In m y specimen the temporal lobe was directed much more forwards (see Plate XXIII.) so as to largely cover the rhinencephalon and conceal a considerable extent of the rhinal fissure. The two hemispheres are unsymmetrical as regards their convolutions, as is usually the case in complexly folded brains; accordingly I describe each separately. Right Hemisphere. The large temporal lobe is directed forwards and is separated from the parietal lobe by the long and deep Sylvian fissure (Plate XXIII. fig. 1, Sy), which measures from end to end about 4 inches. From the upper extremity of the Sylvian fissure two or three small fissures radiate outwards, joining the inner of the longitudinal fissures which traverse the temporal lobe. Just before the extremity of the Sylvian fissure an evidently important (because deep), though short, fissure runs upwards at right angles, or nearly so, to the Sylvian fissure ; this fissure just stops short of joining the conspicuous fissure of Eolando. It is, perhaps, to be compared to the ascending limb of the Sylvian fissure in other Mammalia. Anteriorly to this there is a deep fissure which I regard as being possibly comparable to the fissure of Rolando (Plate XXIII. fig. 1, F.R). It reaches the Sylvian fissure below, and runs obliquely upwards, reaching to within about f of an inch of the median interhemispheral sulcus. When the brain is viewed from above this fissure of Rolando, if I am right in so identifying it, is seen to divide the hemisphere into approximately two halves. The importance of this furrow was unluckily illustrated by the hemisphere breaking into two halves at this point, a result largely due of course to its great depth and extent. Still in front of this is another important fissure which divides also into two branches, in the fashicm. of the letter T, and in front of this again a second also |