1881.J NATURAL SCIENCES OF PHILADELPHIA. 131 



compartments, &, c, d and e (Plate XII) ; the first, h, however, 

 not being so apparent externall}' as the other three (shown in 

 Plate XI, fig. 3). The oesophagus, a (Plate XII), opens freely 

 into the compartment 6, which is situated posteriorly, and which 

 might be easily overlooked unless opened. I propose calling this 

 compartment the first stomach, as the food can pass from the 

 oesophagus into it without necessarily passing into either of the 

 other two stomachs, c and d, whereas the food must pass through 

 a small part at least of b in order to get into c or d. This is 

 due to a peculiar disposition at the entrance of the stomachs c 

 and d (Plate XIII). At this point the lining membrane is 

 raised up into two valvular folds, g and h (PI. XIII), of which the 

 former is the best developed. The fold g almost divides the 

 second stomach into two parts. These folds are 10 and 4 inches 

 in length respectively, and abovit the ^ of an inch in breadth, and 

 contain muscular fibres. When these folds are approximated the 

 oesophagus, a, and first stomach, &, are completely shut off from c 

 and d. When, however, the valvular folds are separated, then 

 the food can pass from the oesophagus, a, or from stomach, 6, 

 over the edges of the folds, g and h, into either the stomachs, c 

 or d. As the compartment d passes into e, which is continuous 

 with the intestine, /", it appears to me that the two compartments 

 may be appropriately called the third and fourth stomachs, in 

 which case c would be the second one. 



From a simple inspection of the stomachs of the Hippopotamus, 

 one would be disposed to conclude that the animal was a rumi- 

 nant. As the act of rumination, however, has never been observed 

 in the Hippopotamus, either in captivity or in the wild state, so 

 far as is known, the inference must be that the food passes either 

 directl}^ from the oesophagus into the second or third stomachs, as 

 is probably the case with liquids, or into the first stomach, and 

 then indirectly into the second or third, when more solid articles 

 are introduced. 



The four stomachs differ considerably in size, the third, d^ being 

 by far the largest ; it measured from right to left 27 inches, as seen 

 in situ in PI. XII ; it overlaps, when viewed from the anterior sur- 

 face, the second and fourth stomachs, c and e, and, to a great 

 extent conceals the first stomach, &, especially when the latter is 

 empty. The first stomach, b, measured 15 inches from right to 

 left, and is so closel}^ united to the third one, d, that externall}^ 



