366 University of California Publications in Zoology [Vol. 11 



in form by the total loss of barbs on the main shaft, which is 

 stiff and straight ; and the rictal, loral and supra- and post- 

 orbital bristles are adapted by their coarse, open structure, and 

 lack of soft or superfluous parts, to cover those parts of the 

 face where ordinary contour feathers would be subjected to an 

 undue amount of wear and tear and soiling. 



Transmitted June 27, 1913. 



LITERATURE CITED 



BONHOTE, J. L. 



1912. On a peculiar type of feather in the water rail. British Birds 

 (London), 5, 42-44. 1 fig. in text. 



Headley, F. W. 



1912. The flight of birds (London, Witherby & Co.), x -f- 163, 16 pis., 

 27 figs, in text. 



NiTZSCH, C. L. 



1867. Pterylography. Trans, from the German, ed. by Sclater, P.L. 

 (London). Bay Soc. Pub!., x -|- 181, 10 pis. 



Pycraft, W. p. 



1893. On the interlocking of the barbs of feathers. Nat. Sci., 3, 

 197-203, 6 figs, in text. 



Riddle, O. 



1908. The cause of the production of "down'' and other downlike 

 structures in the plumages of birds. Biol. Bull., 14. 163-17.5. 



Strong, E. M. 



1902. The development of color in the definitive feather. Bull. Mus. 

 Comp. Zool. Harvard College, 40, 147-184, 9 pis. 



Wray, E. S. 



1887. On some points in the morphology of wings of birds. Proc. 

 Zool. Soc. London, 1887, 343-357, pis. 29-32, 2 figs, in text. 



