312 MB. r, E. BEDDAED ON THE [Mar. 28, 



and African Elephants. The internal lateral, superficial, and ex- 

 ternal lateral aspects are figured. 



I shall now proceed to describe the brain examined by myself. 



Desceiption oe the Beain. 



The outlines of the hemispheres (Plate XXII.) are not by any 

 means exactly as have been depicted by Krueg ; the compara- 

 tively narrow anterior half is, in my specimen, barely so long as 

 the broader posterior section ; the lengths in my specimen were 

 (rather rougldy) 4^ and 3 inches respectively. It seems likely, 

 therefore, that the general form of the hemispheres in this Elejihant 

 may now be fixed with something like certainty, and that the diiFer- 

 ences 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 aboA e. I 

 did not find that the rhinal fissure had so long a visible course upon 

 the lateral aspect of the bi'aiu 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 my 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 uusymmetrical as regards their con- 

 volutions, as is usually the case in complexly folded brains ; 

 accordingly I describe each separately. 



Right Uemisjphere. 



The large temjporal lobe is directed forwards and is separated from 

 the parietal lobe by the long and deep Si/Ivianjissure (Plate XXIIL 

 fig. 1, Sy), which measures from end to end about 4 inches. Erom 

 the upper extremity of the Sylvian fissure two or three small 

 fissui-es radiate outwards, joining the inner of the longitudinal 

 fissures which traverse the temporal lobe. Just before the ex- 

 tremity 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 fissui-e of Polando. It is, perhaps, to be compared 

 to the asccndin;/ limb of the Sylvian fissure in other Mammalia. 

 Anteriorly to this there is a deep fissure which I regard as being 

 possibly comparable to t\\Q fissure of liolando (Plate XXIII. fig. 1, 

 F.R). It reaches the Syhdan fissure below, and runs obliquely 

 upwards, reaching to within about | of an inch of the median 

 interhemispheral sulcus. When the brain is viewed from above 

 this fissure of Polando, if I am right in so identifying it, is seen to 

 divide the hemisphere into approximately two halves. The im- 

 portance of this furrow was unluckily illustrated by the hemi- 

 sphere 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 t^^•o branches, in 

 the fashion of the letter Y-, and in front of this again a second also 



