TEE DIGESTIVE APPARATUS OF BIRDS. 



513 



degeneration. There are no permanent glands for this secretion.* Pigeons 

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

 existence. 



Fig. 305. 



GENERAL VIEW OF THE DIGES- 

 TIVE APPARATUS OF A FOWL. 



The abilorninal muscles h:ive been 

 removed, :is well a.s the ster- 

 num, heart, trachea, the greater 

 portion of the neck, and ail 

 the head except the lower jaw, 

 which ha.s been turned .i.side to 

 show the tongue, the phaiynx, 

 and the entrance to the larynx. 

 The left lobe of the liver, suc- 

 centric ventricle, gizzard, and 

 intestinal mass, have been 

 pushed to the right to exhibit 

 the difl'erent portions of the 

 alimentary canal, and to ex- 

 pose the ovary and oviduct. 



1, Tongue ; 2, pharynx ; 3, first 

 portion of the oesophagus ; \, 

 crop ; 5, second portion of the 

 oesophagus •, 6, succentric ven- 

 tricle ; 7, gizzard ; 8, origin 

 of the duodenum ; 9, first 

 branch of the duodenal flex- 

 ure; 10, second branch of tiie 

 same; 11, origin of the float- 

 ing portion of the small in- 

 testine; 12, small intestine; 

 12', terminal portion of this 

 intestine, flanke i on each side 

 by the two cxca (regarded as 

 the analogue of the colon of 

 mammals); 13, 13, free ex- 

 tremities of the cffca; 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 

 biliai'y ducts; the two pan- 

 creatic ducts are the anterior- 

 most, the choledic or hepatic 

 is in the middle, and the cystic 

 duct i> [losterior; 23, pancreas; 

 24, diaphragmatic aspect of 

 the lung ; 25, ovary (in a state 

 of atrophy) ; 26, oviduct. 



' ll-antt^T. Obseri-dlioiis on certain parts of the Animal Economy. London: 1792. Duvernoy, 

 in G. Cuvier, iecons d'Anatomie Compar^e. 2nd Edition. Paris: 1836. Charbonelk-Salle 

 and Phisalix, Snr In Secretion Lad^e de Pigeona fi Tncuhnfion in Comptes Rendu de I'Academie 

 des Sciences. 1886. 



