THE DIGESTIVE APPARATUS OF BIRDS. 



513 



degeneration. There are no permanent glands for this secretion.^ 

 exclusively nourish their yoimg with this fluid during the first three days of "their 



existence. 



F5g. 305. 



GENERAL VIEW OF THE DIGES- 

 TIVE APPARATUS OF A FOWL. 



The abdominal muscles have been 

 removed, as well as the ster- 

 num, heart, trachea, the greater 

 portion of the neck, and all 

 the head except the lower jaw, 

 which has been turned aside to 

 show the tongue, the pharynx, 

 and the entrance tn the larynx. 

 The left lobe of the liver, suc- 

 centric ventricle, gizzard, and 

 intestinal mass, have been 

 pushed to the right to exhibit 

 the diiferent portions of the 

 alimentary canal, and to ex- 

 pose the ovary and oviduct. 



1, Tongue ; 2, pharynx ; 3, first 

 portion of the oesophagus ; 4, 

 crop; 5, second portion of the 

 (Esophagus; 6, succentric ven- 

 tricle ; 7, gizzard ; 8, origin 

 of the duodenum ; 9, first 

 branch of the duodenal flex- 

 ure ; 10, second branch of the 

 same; 11, origin of the float- 

 ing portion of the small in- 

 testine ; 12, small intestine; 

 12', terminal portion of this 

 intestine, flanked on each side 

 by the two caeca (regarded as 

 the analogue of the colon of 

 mammals); 13, 13, free ex- 

 tremities of the caeca; 14, 

 insertion of these two culs-de- 

 sac into the intestinal tube; 

 15, rectum ; 16, cloaca ; 17, 

 anus; 18, mesentery; 19, left 

 lobe of the liver; '20, right 

 lobe; 21, gall-bladder; 22, 

 insertion of the pancreatic and 

 biliary ducts ; the two pan- 

 creatic ducts are the anterior- 

 most, the choledic or hepatic 

 is in the middle, and the cystic 

 duct is posterior; 23, pancreas; 

 24, diaphragmatic aspect of 

 the lung ; 25, ovary (in a state 

 of atrophy) ; 26, oviduct. 



" Hunter, Observations on certain parts of the Animal Mconomy. London : 1792. Duvernoy, 

 inG. Q,\xyKX,Legons d'Anatomie Comparee. 2nd Edition. Paris: 1836. Charbonelle-Salle 

 and Phisalix, Sur la Secretion Lact€e de Pigeons en Incubation, in Comptes Rendu de I'Academie 

 des Sciences. 1886. 



