THE ALIMENTARY CANAL 



287 



as the turkey, have 

 near the lower end 

 of the gullet" The 

 ostrich, goose, swan, 

 most of the waders, 

 and the fruit or 

 insect-eating birds, 

 which find their 

 food in tolerable 

 abundance, and take 

 it in small quanti- 

 ties, have no such 

 reservoir. Pigeons 

 have a double crop. 

 In all birds, the 

 food passes from 

 the gullet into the 

 proventriculus, or 

 stomach proper, 

 where it is mixed 

 with a " gastric 

 juice" secreted 

 from glands on the 

 surface. Thence it 

 goes into the giz- 

 zard, an oval sac 

 of highly muscular 

 texture, and lined 

 with a tough, horny 

 skin. 100 The giz- 

 zard is most highly 

 developed, and of a 

 deep-red color,, in 

 the scratchers and 

 flat-billed swimmers 



a pouch, called the crop, developed 



FIG. 248. Digestive Apparatus of the Fowl: i, 

 tongue; 2, pharynx; 3, 5, esophagus; 4, crop; 

 6, proventriculus; 7, gizzard; 8, 9, 10, duodenum; 

 n, 12, small intestine; 13, two caeca (analogue of 

 the colon of mammals') ; 14, their insertion into the 

 intestinal tube; 15, rectum; 16, cloaca; 17, anus; 

 18, mesentery; 19, 20, left and right lobes of liver; 

 21, gall bladder; 22, insertion of pancreatic and 

 biliary ducts; 23, pancreas; 24, lung; 25, ovary; 

 26, oviduct. 



(as fowls and swans) ; but compara- 



