538 Proceedings of Royal Society of Edinburgh. [sess. 
of the great omentum to become blended with the 'ventral 
layer. 
From the above it will be seen that, though there is some 
approximation to the condition as found in man, both mesentery 
and mesocolon have retained much of their primitive disposition. 
The attachment of the great omentum along the right side of the 
dorsal abdominal wall appears to he altogether peculiar. 
In Lagothrix the condition of affairs is not so involved as it is 
Fig. 6. 
in Cercocebus. At the same time it is important to notice that, 
comparatively low though Lagothrix is among primates, the human 
arrangement is approximated in connection with the ascending 
colon. In this animal the great omentum is very short, and 
presents little of interest, except that it practically does not exist 
in connection with the extreme right of the stomach. What 
little there is of it is tucked up into the interval circumscribed by 
the stomach, the spleen, and the splenic flexure of the colon ; so that, 
