142 MR. P. CHALMERS MITCHELL ON THE [Jan. 14, 
is longer than the others, as frequently happens when the caca 
are relatively short. It is drained partly by the duodenal vein. 
Fig. 5. 
Colymbus septentrionalis ; intestinal tract. ., short-circuiting vessel from 
duodenal to posterior mesenteric vein cut across. 
The last part of the intestine is long and straight, and the poste- 
rior mesenteric vein drains the ceca and part of the region in 
front of the ceca. 
SPHENISCIFORMES. 
In these (fig. 6) the primitive arrangement is disguised by the 
enormous length of the gut and consequent complexity of the 
Fig. 6. 
KGB 
Eudyptes chrysocome ; intestinal tract. , short-circuiting vessel cut across, 
