428 



ANATOMY OF VERTEBRATES. 



324 



In the Mole the abdominal oesophagus is long and enters the 

 stomach midway between the two ends : the cavity, when distended 

 with the worms and grubs devoured by this voracious burrower, 

 ' fills nearly half of the abdomen.' ■ In the Tenrecs ( Centetes) the 

 cardia and pylorus are further apart than in most Insectivora : the 

 cardiac sac is less prominent ; the pyloric end is bent upon itself. 

 As a rule the intestinal canal is uniform in diameter, and devoid 

 of caecum in the present order : it is loosely suspended on one con- 

 tinued peritoneal fold from the beginning of the duodenum to the 

 rectum. In the common Shrews, fig. 359, the intestine is about 

 four times the length of the body ; in the Hedgehog about six 



times, in the Mole seven times, that 

 length. The Tupaias and some of 

 the snouted-shrews are exceptions : 

 in the former ( Cladobates) the caecum 

 is simple, straight, about an inch in 

 length, not wider than the major 

 part of the colon ; and but little 

 wider than the ileum. Macrosce- 

 lides has a long, slender, pedunculate 

 caecum. In Rhynchocyon, the caecum, 

 fig. 324, c, is about 3 inches long, and 

 is twice the width of the ileum, ib. i. 

 The colon, of similar diameter with 

 the caecum, forms a short double bend, 

 r, r, returning upon itself, before it 

 is continued on into the narrow por- 

 tion ending in the rectum. 

 The lining membrane of the Mole's intestine is disposed, 

 along part of the canal, in close-set longitudinal folds ; but is re- 

 markable for its smoothness and absence of visible villi. The 

 mucous membrane of the Hedgehog's intestine is beset with 

 minute flat, conical villi, changing toward the end of the canal 

 into a fine reticulate surface. 



§ 328. Alimentary canal of Cheiroptera. — The Cheiroptera 

 present three forms of stomach ; one relating to vegetable diet, 

 another to the times of taking the food and to the quantity taken, 

 a third to the ordinary capture of insects during flight. The latter 

 relation, which prevails in the order, is associated with a form of 



Caecum aud colon, Proboscidian Shrew. 



LXXXIV'. 



elytrse, wings and legs of insects, including those of the Scarabceus and of Geotrupes 

 stercorarius ; from November onward to March — the hybernating season — there was 

 no food in the stomach, only a little creamy mucus, ccxxxvi. vol. ii. p. 193. 

 1 Ib. p. 187. 



