170 



THE VITAL FUNCTIONS. 



Ilyrax, (Fig. 307). The first, or cardiac portion, is 

 often lined with cuticle, while the lower portion is 



306 



not so lined ; as is seen very conspicuously in the 

 stomachs of the Solipeda. The stomach of the 

 Horse, in particular, is furnished at the cardia, with 

 a spiral fold of the inner, or cuticular membrane, 

 which forms a complete valve, offering no impedi- 

 ment to the entrance of 

 food from the oesophagus, 

 but obstructing the return 

 of any part of the contents 

 of the stomach into that 

 passage.* This valve is 

 shown in Fig. 311, which 

 represents an inner view 

 of the cardiac portion of 

 the stomach of the horse ; 

 o being the termination 

 of the oesophagus. 



* The total inability of a horse to vomit is probably a consequence 

 of the impediment presented by this valve. See Mem. du Museum 

 d'Hist. Nat. viii. 1 i 1. 



