Osteology of the Numididsc, 



339 



for the swollen extremity of the furcula^ which lodges a loop 

 of the windpipe; but in all Guinea-fowls the carina seems 

 to be deeper than in Gallus(see figs. 1, 2, p. 337). In galli- 

 naceous birds generally, as is well known, the spina externa 

 and the spina interna sterni unite to form a broad, or rather 

 deep, plate of bone in which the sternum ends anteriorly. 

 This is perforated below by a foramen, through which pass 



Fig. 4. 



Sternum of Galh(s bankiva. 

 (Dorsal aspect, § nat. size.) 



the inner edges of the coracoids. The form of the manu- 

 brium differs in different Guinea-fowls : in the two species 

 which are referred to the genus Guttera the manubrium is 

 longer and with a more sinuous outline, ending in front in a 

 more pointed extremity. In A'^. meleagris, N. vulturina (fig. 1, 

 p. 337), N. mitrata, and A^. ptilorhyncha it is shorter and 

 squarer ; and, moreover, the upper face of its base is perfo- 

 rated by a conspicuous pneumatic foramen, which latter is 



