\ h CO J 





There i- no longer any doubt, it may be added, U to the -\- 

 identity of thcM- foil 



\e\t to Lepidoptera, Odonata mo>l frequently -how (olorati 

 anl iueny. The male of ( '<ilo jitcrvx w<i< ul<i(<! is velvet y bla< k ; I he female 

 smoky, with a white />tcros(ixni<i(<il spot. AmoiiL' Coleoptera, the male 

 of //opliti Irij'iiscidlti is grayi>h and the female reddish brou 

 more examples might be 



en, though sexual dif- 

 fercnces in coloration are 

 comparatively rare among 

 beetles. < )f Hymenoptera, 

 some of the Tenthredinida- 

 exhibit coloratioiiji 1 

 intigeny, 



Among tropical butter- 

 iiic- there are not a few 

 instances in which the 

 special coloration of the 

 female is adaptive har- 

 monizing with the sur- 

 roundings or else imitating 

 with remarkable precision 

 the coloration of another 

 species which is known 

 to be immune from the 

 attacks of birds as de- 

 x ribed beyond. In this 

 way, as Wallace suggests, 

 the eirg-laden females may 



escape destruction, as they ^^^ ^^^ 



sluggishly seek the proper FlG 239 ^ Callosamia ^^ A , male , clinging to 



plants Upon which tO lay cocoon; B, female. Reduced. 



their eggs. Here would 



be a fair field for the operation of natural selection. 



In most insects, however, sexual differences in coloration are ap- 

 parently of no protective value and are usually so trivial and variable 

 fl probably to be of no use for recognition purposes. The usual state- 

 ment that these differences facilitate sexual recognition is a pure as- 

 sumption, in the case of insects, and one that is inadequate in spit 

 its plausibility, for d) it is extremely improbable from our present 



