REPORT ON THE SPHENISCID^. 



35 



The Phalanges. 



The first or radial metacarpal is destitute of any phalanx, the second or middle 

 metacarpal is provided with two phalanges, and the third or ulnar metacarpal with a 

 single phalanx. 



ThQ first i^halanx of the second finger is oblong in form, and is much compressed. 

 Its inner surface is almost flat, while the outer is slightly convex. Its radial and ulnar 

 borders are parallel. Its upper and lower extremities are each provided with a flat 

 articular surface, one of which articulates with the lower extremity of the middle 

 metacarpal bone, the other with the base of the second phalanx of the same finger. 



This bone presents the same form in every species of Penguin. Its dimensions are 

 given below in inches. 



Species. 



Eudyptes chrysoeonie, from Tristan, 



Eudyptes chrysoeonie, from the Falklands, 



Eudyptes chrysocome, from Kerguelen, 



Eudyptes ehrysolophus, 



Spkeniseus demersus, 



Spheniscus magellanicus, 



Spheniscus mendiculus, 



Spheniscus minor, 



Pygosceles tceniattis, . 



Aptenodytes longirostris. 



Length ot first 

 phalanx of middle 

 metacarpal bone. 



Breadth of first 

 phalanx of middle 

 metacarpal bone. 



1 

 1 

 1 



n 

 n 



i 



n 



The second phalanx of the second finger is triangular in form, and narrows gradually 

 from its base to its distal extremity. On the radial border of the bone, close to its base, 

 is a small osseous tubercle, which slightly overlaps the end of the first phalanx. The 

 articular surface of the bone is oval, and articulates with the first phalanx. Its distal 

 ^ extremity is pointed. Like aU the other bones of the wing it is much flattened 

 from side to side. Its form is the same in every species of Penguin. 



