514 Proceedings of Royal Society of Edinburgh. [sess. 
The degree of sacculation is very variable in different parts of 
the large intestine. The caecum has no sacculations, hut they are 
well marked in the ascending colon, and in A and B (especially in 
the initial part of B), and in the narrow piece of colon marked + 
(PL II. fig. 4). Sacculations are very faintly indicated, and few in 
number, in C and D. 
Pancreas . — A lengthy description of the pancreas of Cercocebus 
is not necessary, for it bears a remarkably strong resemblance, both 
in form and position, to the organ as described in the average 
text-book on human anatomy. Its head is in contact vdth the 
entire length of the duodenum. The rest of it crosses the middle 
line to come into relation with the cephalic part of the ventral 
surface of the left kidney ; the blunt tail touching the spleen. 
Liver. — It is regrettable that, though a considerable volume of 
work has been done on the surface anatomy of the mammalian 
liver, there should still be some lack of uniformity in the methods 
of description employed by various writers in their discussion of 
the lobes, etc., of the liver of the particular animals upon which 
their attention has been bestowed. No doubt this is due to the 
slow-dying notion that the human liver should be taken as the 
type. That the liver of man has been considerably modified in 
the evolution of the erect attitude has been deduced from com- 
parative anatomy by various authors. Keith (11), for example, 
has averred that the consolidation and absence of fissures in man 
and the anthropoid apes is the result of the upright posture. In 
anthropoids, with an erect position during locomotion, the dorsal 
mesentery, says Keith, has acquired all the complicated attachment 
seen in man, with the result that the viscera are more firmly and 
extensively fixed to the dorsal wall of the abdomen than obtains 
in pronogrades. This more extensive fixation of the liver to the 
dorsal abdominal wall is accompanied by the disappearance of deep 
fissures in the liver. This writer also points out that the change 
in form of the thorax and abdomen in anthropoids has had an 
effect upon the form of the liver. Huge goes even further than 
Keith, and, after showing that the trunk of all primates has 
undergone a change in form (12), states that the remodelling of 
the liver of primates depends upon a change in the entire trunk, 
accompanied by an alteration in form of the diaphragm, which has 
