4+8 RLE ME N'T A RY A KA TOM Y. [LESS. 



as in the Opossum and others. It may be wanting altogether, 

 as in the Hedgehog, Weasels, Porpoise, and others. 



A vermiform appendix is very rarely found except in 

 man. It exists, however, in the highest Apes and in the 

 Wombat ; while in the Monotremes there is a small worm-like 

 cae um which suggests the belief that this appendix in the 

 Wombat is but an abruptly atrophied condition of the free 

 end of the caecum a belief strengthened by the condition 

 found amongst Lemuroids, which have a very long caecum, 

 drawn out into an elongated conical termination. 



The caecum may bifurcate, as in the Manatee ; or there 

 may be two small caeca, as in the Two-toed Ant-eater 

 (Cyclothorus\ or two larger ones, as in the Armadillo 

 (Dasypus sexcinctus) ; or, finally, there may be as in the 

 Hyrax three caeca, one at the usual situation, and two side 

 by side projecting from the colon. A double caecum is a very 

 rare condition in man's class, but it is the. rule in the class 

 of Birds (Fig. 378, e). 



The large intestine, instead of having a form and arrange- 

 ment as in man, may have its various regions elongated and 



FIG. 379. SECTION OF THS STOMACH AND PART OF THE INTESTINES OF A 

 SHARK (Squaliis maximus). 



ce, oesophagus ; c, cardiac part of the stomach ; py, its pyloric part ; s, the 

 spleen ; d, the duodenum ; />, a band containing six hepatic ducts ; cli, a 

 dilatation in which these six ducts terminate ; z, the intestine, provided with a 

 spiral valve. 



convoluted, or the whole greatly augmented in length and 

 reduced in diameter, and coiled in a peculiar and character- 

 istic manner, as e.g. in the Sheep. 



Valvulae conniventes, absent even in the species most allied 

 to man. reappear in an exaggerated form in the small intes- 



