1 G Memoir up6n livmg and fossil Elephants, 



that the summit of the head is almost round in the African 

 elephant, and that it rises in the Indian elephant into a kind 

 of double pyramid. 



This summit answers to the occipital arcade of man and 

 other animals, and is so high in the elephant merely for the 

 purpose of giving to the occipital face of the cranium a suf- 

 ficient extent for a cervical ligament and occipital muscles, 

 proportionate to the weight of the enormous mass they have 

 to support. 



This difference in the form of the summits proceeds from 

 the difference in the inclination of the frontal line, which 

 retreats much further in the African elephant, where it 

 forms with the occipital line an angle of 115°, than in the 

 Indian elephant, where it makes an angle of 90° only. 



From this come the principal differences of the profile, 

 such as, 1st, The proportion of the vertical height of the 

 head at the distance from the end of the bones of the nose 

 to the occipital condyles, which are nearly equal in the 

 African elephant, (being as 33 to 32,) and the first of which 

 is nearly one-fourth larger in the Indian elephant (being 

 as 24 to 19). 2d, The proportion of the distance from 

 the edges of the alveoli of the tusks at the summit to a line 

 which is perpendicular to it and goes from the end of the 

 bones of the nose to the anterior edge of the occipital hol- 

 low. The first of these lines is almost double that of the 

 other in the Indian elephant (being as 26 to 14). It is little 

 less than one -fourth larger in the African elephant (being 

 as 21 to 16). 



Besides these in the proportions, there are also differences 

 in the contour: Ist, The front of the Indian elephant is 

 followed into a sinking and concave curve ; that of the 

 African elephant is on the contrary a little convex. 2d, 

 The sub-orbitary hole is larger in the Indian dephant. In 

 the African, It resembles a channel rather than a simple hole. 

 3dly, The temporal hollow is rounder in the African ele- 

 phant ; and the apophysis, which distinguishes it from the 

 orbit, is thicker than in that of India, in which this hollow 

 has g,p oval contour. 



When 



