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tarsus. The ankle-joint is intertarsal, the succeeding bone, 

 the long tarso-metatarsus, being composed of the distal 

 tarsals fused with metatarsals 2, 3 and 4. The first meta- 

 tarsal is small and free. The foot or pes has four toes ; 

 the first has two, the second three, the third four, and the 

 fourth five phalanges. 



Name the Muscles of Flight, state their Specific Functions, 

 and give their Origins and Insertions. 



The pectoralis major, the largest, depresses the wing ; 

 it arises from the sternum (lateral portion), keel (ventral 

 half) and clavicle, and it is inserted on the humerus (ventral 

 surface). 



The pectoralis minor (subclavian or supracoracoideus), 

 smaller than and covered by the former, arises from the 

 sternum (inner portion) and the keel (dorsal half). It is 

 inserted on the humerus (dorsal surface). Its tendon passes 

 through the foramen triosseum, which serves like a pulley. 

 When the muscle contracts, it raises the wing. 



The small coraco-brachialis arises mainly from the outer 

 border of the coracoid, and is inserted on the head of the 

 humerus. It assists in depressing the ring. 



Describe the Alimentary System of the Pigeon. 



From the buccal cavity the short pharynx leads into a 

 long gullet or oesophagus which expands, at the base of 

 the neck, into a large storing crop. Continuing from the 

 crop, the gullet leads into the wider proventriculus,* which 

 secretes the digestive juice. Succeeding this is the muscular 

 gizzard ; it contains the small stones swallowed by the 

 bird, and its horny inner walls form a mill for crushing the 

 food. The duodenum, which issues from the gizzard near 

 the opening of the proventriculus, forms a U-shaped loop ; 

 it is followed by the long and convoluted small intestine. 

 Two small rectal coeca indicate the beginning of the short 

 rectum which opens into the cloaca. 



The bilobed liver (without a gall-bladder) has two separate 

 bile-ducts, opening into the proximal and distal parts of 

 the duodenum. The pancreas is situated in the duodenal 

 loop ; and there are three pancreatic ducts, opening into 

 the distal portion of the duodenum. The abdominal 

 viscera are covered by a fat-laden fold of mesentery, the 

 great omentum. 



* Attached to its right side there is a small red organ, the 

 spleen. 



