DIGESTIVE ORGANS OF THE GALLINACEA. 



527 



Fig. 229. 



cavity, in the shape of a funnel, called ventriculus succenturiatus, pro- 

 ventriculus, infundibulum or second stomach. This is seated in the 

 abdomen, and is generally smaller than the former. It is usually 

 thicker than the oesophagus, partly owing to its numerous glands, which 

 are very large and distinct in many birds. In the ostrich, they are as 

 large as the garden-pea, and have very manifest orifices. The infun- 

 dibulum terminates in the ventriculus callosus, gizzard or third stomach 

 the most curious of all the parts of the apparatus. Figs. 228 and 

 229 afford an external and internal view of the gastric apparatus of 

 the turkey ; a, representing the oesophagus immediately below the 

 crop, covered with cu- 

 ticle ; bj the openings 

 of the gastric glands 

 in the second stomach, 

 placed on a surface, 

 that has no cuticular 

 covering ; , horny 

 ridges, between the 

 gastric glands and the 

 lining of the gizzard ; 

 dj a minutely granu- 

 lated surface between 

 the cavity of the giz- 

 zard and duodenum; 

 and e, the inner sur- 

 face of the duodenum. 

 Fig. 228 accurately 

 represents the mode in 

 which the second sto- 

 mach terminates in the 

 gizzard, and the latter 

 in the duodenum; the 

 gizzard forming a kind 

 of pouch depending 

 from the alimentary 

 canal. The gizzard is 

 usually of a globular 

 figure, flattened at the 

 sides, and is considered 

 to consist of four mus- 

 cles, remarkable for 

 their great thickness and strength; a large hemispherical pair at the 

 sides, and a small pair situate at the extremities of the stomach. The 

 gizzard is covered externally by a beautiful tendinous expansion ; and 

 is lined by a thick, strong, callous coat, which appears to be epider- 

 mous in its character. On this are irregularities, adapted to each 

 other on the opposite surfaces. The cavity of the organ is remarkably 

 small, when compared with its outward magnitude, and its two orifices, 

 represented in Fig. 228, are very near each other. In the pouch 

 formed by the small muscles at the lower part of the gizzard, numerous 

 pebbles are contained, which seem to be indispensable to the digestion 



Interior of the Gastric Apparatus of the Turkey. 



