276 CALIFORNIA ACADEMY OF SCIENCES. 



closely ape the appearance of certain diminutive shrikes 

 inhabiting the same country." 



GENUS CROTOPHAGA. THE ANIS. 



(1) Adult male like female; young like adult (but 

 colors lacking the metallic lustre). 



Color entirely black, with dull bluish, greenish, or 

 bronzy reflections. 



This is probably a very old and highly specialized 

 genus of birds, which has reached the limit of pigmen- 

 tation. Sexual selection has probably been a factor in 

 the development of its present plumage, and the black 

 may be a form of directive marking, for the birds are 

 gregarious. 



GENUS GEOCOCCYX. THE ROADRUNNERS. 



(1) Adult male like female; young like adult. 



Prevailing colors brownish, buffy, white, bronze and 

 greenish. 



There seems to be little doubt that this genus has 

 been in past times a brilliantly attired bird, the colors 

 having been developed by sexual selection. These have 

 been lost, either for the sake of protection in the com- 

 paratively open desert country in which the bird is now 

 found, or because the genus is degenerating, or possibly 

 the direct influence of the desert climate may have 

 affected the plumage. The principal reason for holding 

 that the group is a degenerate one in its coloration is 

 that while the exposed edges of the feathers are apt to 

 be dull brownish or buffy, the basal portion and interior 

 of the feather which is largely concealed has the most 

 iridescent bronzy and green colors. 



GENUS COCCYZUS. AMERICAN CUCKOOS. 

 (1) Adult male like female; young like adult, but 

 colors slightly duller, and tail markings less distinct. 

 Prevailing colors, brownish, grayish and white. 



