FKAT11KKS 



11 



The only explanation, so far as I am aware, of this 

 remarkable state of affairs is contained in a suggestive paper 

 by DEGEX.' DEGEN commences with the assumption that in 

 the hands of the primitive bird all three fingers then freely 

 movable were furnished with remiges. In modern birds 

 remiges are only attached to the thumb (ala spuria) and to 

 digit II. DEGEN also postulates a fourth finger (of which 

 rudiments have been discovered in modern birds ; see below) 

 with its remiges. 



When the metacarpal bones became fused the feathers 

 of the third and fourth digits were, he supposed, forced back 



FIG. 2. a. CUBITAL BEMIGES OF PHEASANT, b. CUBITAL KEMIGKS 



OF GOLDEN EAGLE (AFTEU WKAY). 

 li 1-7, remiges : />.<', <lovsal tectris major : J7, ulim. 



upon the ulna, as there was no longer any room for their 

 coexistence with those of the second digit upon the com- 

 pressed hand. Among these the carpal remex was also 

 pushed back. As this remex was attached to an unstable 

 bone or cartilage, its position was not secured, and the varia- 

 bility remained when the feather altered its position ; hence 

 the presence or absence of the fifth remex, which is this 

 feather. 



The carpal remex is another variable feather. It is present 



1 ' On some of the Main Features in the Evolution of the Bird's Wing,' Bull. 

 Brit. Orn. Club, July 1894 (published in I&is). See also for quincubitalism 

 GEKBE, ' Sur les Plumes de Vol et leur Mue,' Bull. Soc. Zool. Fr. ii. Iw77, 

 p. 289. 



