448 



THE BIRDS 



xvi. 7- 



three metacarpals, one short and two long and fused. Only one digit, 

 probably representing the second, is well developed, having two broad 

 phalanges; the third and the first digits consist of single rods, the 



Fig. 260. Various types of feet in birds. 



1, shag (swimming); 2, crow (perching, lifting); 3, ptarmigan (stockinged by 



feathers); 4, jungle fowl (walking, scraping); 5, coot (lobate, swimming); 6, jacana 



(suited for walking on floating plants); 7, sea-eagle (raptorial). (From Thompson, 



Biology of Birds, Sidgwick & Jackson, Ltd.) 



latter, standing somewhat apart at the front of the base of the hand, is 

 capable of independent movement ; it carries the bastard wing (alula or 

 ala spuria). 



The glenoid cavity is formed at the union of a blade-like scapula and 

 a stout coracoid. The former lies horizontally and is attached by 

 muscles to the vertebral column and ribs. The coracoid holds the wing 



