COLOR AND COLORATION 



207 



vety black; the female smoky, with a white pterostigmatal 

 spot. Among Coleoptera, the male of Hoplia trifasciata is 

 grayish and the female reddish brown; a few more examples 

 might be given, though sexual differences in coloration are 



FIG. 236. 



Callosamia promcthea; A, male, clinging to cocoon; B, female. Reduced. 



comparatively rare among beetles. Of Hymenoptera, some 

 of the Tenthredinidse exhibit colorational antigeny. 



Among tropical butterflies there are not a few instances in 

 which the special coloration of the female is adaptive har- 

 monizing with the surroundings or else imitating with remark- 

 able precision the coloration of another species which is known 



