230 STRUCTURE AND CLASSIFICATION OF BIRDS 



in both groups of birds. The sternum in both is unnotched 

 and broader behind than in front. 



In the fore hmb the length of the hand distinguishes 



Fia. 105. — Anconal Aspect of Left 

 Humerus of Micropus melanoleu- 

 cus (after Shufeldt). 

 p.f, pneumatic fossa. 



Fig. 106. — Palmae Aspect of£;same 

 Bone (after Shufeldt). 



both the famihes of the Macrochires, whence, of course, the 

 name. The nearest approach in length of hand is shown 

 in the swallows, petrels, and, oddly enough, in the penguins. 



Fig. 107. — Anconal Aspect of Left 

 HuMBlius of Trochilus Alexandri 

 (after Shufeldt). 



p/f pneumatic fossa. 



Fig. 108 Palmar Aspect of same 



Bone (after Shufeldt). 



The humerus in both families is extremely short ; the radial 

 crest is well developed in both into a long process which 

 curves over the shaft in the Trochilidse, but over the head in 

 the swifts. 



