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tion, while, as might be anticipated, its capacity is large and 

 variously formed. But the several purposes to which the 

 mouth is employed, and the means by which such are 

 effected, it is not my purpose to enter upon at present, 

 except to remark on the absence of the salivary glands, 

 which, in some forms, seem to be represented by mucous 

 follicles that open into the mouth below the side of 

 the tongue. Also that among the carp-like fish the palate 

 is very sensitive, exceedingly vascular, while from numerous 

 small pores mucus of a solvent character exudes, appa- 

 rently to assist the digestion of food which the pharyngeal 

 teeth are masticating. The gastric portion consists of an 

 oesophagus and a stomach, between which a cardiac con- 

 striction is not so frequently observable as a change in the 

 structure of lining mucous membrane. In some fishes 

 there hardly exists any definite line of demarcation between 

 the lower end of the stomach and the commencement of 

 the small intestines, but in many a constriction occurs to 

 this situation, termed the pylorus, which subsequently I shall 

 have to refer to. Occasionally the stomach is situated 

 not in the direct course, but to one side, as it were, of 

 the intestinal canal. A second constriction, marked inter- 

 nally, by a more or less well-defined internal valve, shows 

 where the small intestines terminate and the large ones 

 begin. 



If the intestinal canal is slit up and its inner surface 

 examined, the commencement of the stomach is generally 

 observed to be defined by increased vascularity and a more 

 delicate lining membrane than that existing in the oesopha- 

 gus. Its upper or cardiac orifice is usually larger than its 

 lower or pyloric one, while the form of the entire organ is 

 subject to considerable modification, being usually found in 

 one of the two following divisions : the siphonal, which 



