150 



(Jn the Claws and Spurs of Birds' Winys. 



spending structure is met with in them ; but Dr. Shufeldt 

 was unable to find it in the specimens which he examined, 

 and if its non-existence is confirmed, another item will be 

 added to the many diJBferences which separate the Vultures of 

 the Old World from the so-called Vultures of the New 

 World. 



2. The Claw and Spurs of the Screamer [Chauna derbiana). 



The wing of a Screamer [Chauna derbiana) lately sent to 

 me by a correspondent in Venezuela has supplied a very 

 interesting specimen, as it affords an example of a well- 

 developed claw and two spurs coexisting in tlie same species. 



ST- Sp.i ^^-2' 



Outer surface of end of left wing of Screamer {Chauna derbiana), reduced 

 f , showing two metacarpal spurs (SjJ, Sp. 1) and claw on the first 

 digit (C/). D.\, first digit: PhA, first phalanx j Ph. 2, second 

 phalanx. D.2, second digit: PhA', first phalanx; Ph. 2', second 

 phalanx ; Ph. 3', third phalanx. D. 3, tliivd digit. 



The wing-spurs in the Screamer are well known to be of 

 enormous size, and are no doubt formidable weapons of 

 offence. They are placed one on the proximal and the other at 

 the distal extremity of the coalesced metacarpals, and project 

 nearly in a straight line away from the radial edge. The first 

 spur, which rises from the base of the metacarpal, on the prox- 



