VOL. LXXVII.] PHILOSOPHICAL TRANSACTIONS. gig- 



The rectum near the anus appears, for 4 or 5 inches, much contracted, is 

 glandular, covered by a soft cuticle, and the anus small. I never found any air 

 in the intestines of this tribe ; nor indeed in any of the aquatic animals. The 

 mesenteric artery anastomoses by large branches. 



There is a considerable degree of uniformity in the liver of this tribe of ani- 

 mals. In shape it nearly resembles the human, but is not so thick at the base, 

 nor so sharp at the lower edge, and is probably not so firm in its texture. The 

 right lobe is the larger and thicker, its falciform ligament broad, and there is a 

 large fissure between the 2 lobes, in which the round ligament passes. The 

 liver towards the left is very much attached to the stomach, the little epiploon 

 being a thick substance. There is no gall-bladder ; the hepatic duct is large, 

 and enters the duodenum about ^ inches beyond the pylorus. 



The pancreas is a very long, flat body, having its left end attached to the right 

 side of the first cavity of the stomach : it passes across the spine at the root of 

 the mesentery, and near to the pylorus joins the hollow curve of the duodenum, 

 along which it is continued, and adheres to that intestine, its duct entering that 

 of the liver near the termination in the gut. 



Though this tribe cannot be said to ruminate, yet in the number of stomachs 

 they come nearest to that order ; but here I suspect that the order of digestion 

 is in some degree inverted. In both the ruminants, and this tribe, I think it 

 must be allowed that the 1st stomach is a reservoir. In the ruminants the pre- 

 cise use of the 2d and 3d stomachs is perhaps not known; but digestion is cer- 

 tainly carried on in the 4th ; while in this tribe I imagine digestion is performed 

 in the 2d, and the use of the 3d and 4th is not exactly ascertained. 



The caecum and colon do not assist in pointing out the nature of the food and 

 mode of digestion in this tribe. The porpoise, which has teeth, and 4 cavities 

 to the stomach, has no caecum, similar to some land animals, as the bear, 

 badger, racoon, ferret, polecat, &c. ; neither has the bottle-nose a caecum, 

 which has only 2 small teeth in the lower jaw; and the piked whale, which has 

 no teeth, has a caecum, almost exactly like the lion, which has teeth and a very 

 different kind of stomach. 



The food of the whole of this tribe I believe is fish ; probably each may have 

 a particular kind, of which it it fondest, yet does not refuse a variety. In the 

 stomach of the large bottle-nose, I found the beaks of some hundreds of cuttle- 

 fish. In the grampus I found the tail of a porpoise; so that they eat their own 

 genus. In the stomach of the piked whale, I found the bones of different 

 fish, but particularly those of the dog-fish. From the size of the oesophagus we 

 may conclude, that they do not swallow fish so large in proportion to their size as 

 many fish do, that we have reason to believe take their food in the same way: for 



VOL. XVI. U u 



