102 FALCONID^:. 



into the broad sternum and its deep keel. The 

 clavicles are also strong, and the os furcatorius, 

 which is circular, broad and strong, affords a firm 

 support to the shoulders.* The bill, having a 

 strong tooth in the species most truly rapacious, 

 is really a tearing instrument, as much so as 

 the powerful canines of the Felidae. The legs 

 and feet possess immense muscular power, and 

 the claws, remarkably sharp, are also retractile, 

 (though by a different process,) as among their 

 feline representatives. The intestinal canal and 

 digestive organs present gradations between the 

 membranous pouch of the true birds of prey, to 

 the muscular gizzard of other orders, according 

 to the food they particularly select,f and the 

 former is comparatively short and wide, or narrow 

 and very lengthened ; the latter modification is 

 seen in those which prey on fish, and thus, to a 

 certain extent, those species agree in proportions 

 with the digestive canal of the Ichthyophagous 

 Ferae.J 



In the language of the natural system, the 

 Falconidae are separated into Typical, Subtypical, 

 and Aberrant groups, all of which are so far 

 represented by the birds in our own country ; 



* See some interesting remarks on the anatomy of 

 birds of prey by Mr Yarrell, Zool. Journal, No. X. 

 p. 151. 



t Yarrell, 1. c. 



t See paper by Mr Macgillivray " On digestive organ* 

 of birds," in Mag. of Zool. and Bot. vol. L o. 125. 



