SKELETON OF THE WILD DUCK. THE FEATHERS. 305 



the primaries, and do not have the posterior half of the vane 

 much wider than the anterior half. 



The humerals (figs. 56, 9 and 57, 12) form a group of 

 eight small feathers, of varying length, attached to the anterior 

 half of the humerus. 



B 



FIG. 57. WINGS OF A WILD DUCK WITH THE COVERTS REMOVED 



(Anas boschas). x -|. 



A. Eight wing seen from the dorsal side. B. Left wing disarticulated 

 and seen from the ventral side. (Brit. Mus.) 



1. humerus. 



2. radius. 



3. ulna. 



4. radial carpal. 



5. ulnar carpal. 



6. first phalanx of first digit. 



7. second metacarpal. 



8. third metacarpal. 



9. first phalanx of second digit. 



R. 



10. second phalanx of second 



digit. 



11. remicle. 



12. pennae humerales. 



13. cubitals or secondaries. 



14. metacarpal quills. 



15. ad-digital. 



16. mid-digitals. 



17. pre-digital. 



20 



