424 PHILOSOPHY OF ZOOLOGY. 



the substance of the tongue, expedite the progress of the 

 food into the gullet. 



The salivary glands are four in number, and are placed 

 in pairs. The first pair, seated on each side of the mus- 

 cular bed of the mouth, are divided into numerous lobes, 

 the excretory ducts of which pour their fluid into the be- 

 ginning of the gullet. The second pair, seated lower down 

 and below the eyes, are not so much divided, and send out 

 separate canals, which unite and pour their contents into 

 the mouth. 



The guUet is furnished with a lateral expansion, not un- 

 like the crop of galUnaceous birds. The stomach is mus- 

 cular, like the gizzard of fowls, and the cuticle is thick, 

 and separates easily from the other membranes. At the 

 pyloric opening of the stomach, there is another aperture 

 equally large, which leads into the spiral stomach, or cae- 

 cum, as it has been improperly termed by some anatomists. 

 It may with greater propriety be denominated the duode- 

 num, as it performs some of the offices of that part of the 

 gut in the higher orders of animals. This stomach is coni- 

 cal, closed at the distal extremity, and performs about a 

 turn and a half, like a spu-al shell. Its inner surface is 

 covered with a ridge, which traverses it in a closely spiral 

 direction. The. bile flows into it near the apex, and to- 

 wards its base glandular orifices, pouring out a thick, yellow 

 fluid, may be observed. The intestine, after leaving the 

 pylorus, in some species, makes one or two turns, in others, 

 it proceeds directly to the anus. This opening is sealed at 

 the base of the funnel, on its posterior or dorsal side. 



The liver is of considerable size, of an orange-yellow co- 

 lour, and of a soft and spongy texture. It gives rise to 

 two hepatic ducts, which proceed to the extremity of the 

 spiral stomach, where, by a conmion orifice, they empty the 

 orange-coloured bile which they contain. 



