452 



ANATOMY OF VERTEBRATES. 



part in the Manis. 1 In all Sloths the duodenum is loosely sus- 

 pended, and is continued without constriction of mesentery into 

 the rest of the small intestines, which is disposed in many short 

 convolutions, and enters a short and straight colon, without a 

 caecum. The anus is not distinct from the vulva. 



333. Alimentary canal of Cetacea.- -The first peculiarity to be 

 noted in this order is the small area of the gullet in the largest 



species, especially in the 

 great Whale-bone Whale 

 (Balcena mysticetus} : its 

 lining membrane is here 

 disposed in longitudinal 

 folds which close the area 

 of the tube in the con- 

 tracted state : they are 

 coated by a thick irregu- 

 larly rugous epithelium, 

 and are connected with 

 the strong muscular coat 

 by a deep layer of elastic 

 cellular substance. The 

 stomach is complex, di- 

 vided into several cavi- 

 ties, in all true Cetacea. 

 In the Porpoise (Plwccena 

 communis], fig. 355, the 

 first cavity is continued 

 in the same line with the 

 oesophagus, having the 

 same structure, and not 

 being divided from it by 

 any sensible constriction ; 

 its commencement is in- 

 dicated by the orifice 

 leading into the second 



Stomach, liver, and spleens, of the Porpoise. CXLIV". (From stomach, beyOlld which 

 a drawing by 11. O. the prep, dry, is iu Mus. Coll. Chir.) . . , . -, . 



orifice it is continued in 



the form of a dilated ovate cavity, ib. a, a. It is lined with a 

 cuticle, or thick laminated epithelium, and its inner surface is 



1 The fig. 354 has been taken l>y the writer of CL". from cxxn'. vol. xiii. pi. m., 

 fig. 2. The foregoing description is from dissection of the specimen of Chofapus didac- 

 tyhis which died at the London Zoological Gardens, in 1851, and in which the arteries, 

 were previously injected. Sec cxi.vn". p. 1G7, No. 553 c. 



