184 DIVERSITY OF THE SEXES 



peculiarity, we should anticipate albinism in the 

 cool, melanism in the hot season. 



Albinic antigeny similar to that of our Clouded 

 Sulphur may be seen more rarely in neighboring 

 genera, south of New England ; it is, however, 

 common both in this country and in Europe to 

 nearly all the species of the genus Eurymus, and 

 it need not surprise us to find that in the high 

 north and at great altitudes, species occur all 

 whose females are pale ; the colorational antigeny 

 has become complete instead of partial. The 

 same is the case with the melanic 

 antigeny in many blues ; there are 

 exceedingly few species which have 

 both brown and blue females ; 

 but brown females with blue males 

 is a common phenomenon in Eu- 



Nicippe, nat. size. -, ,-, i -i _c < 



rope and in the western half of 

 our own country. 



But there is also a colorational antigeny quite 

 apart from albinism or melanism, which may be 

 expressed in various ways ; in all such cases, so 

 far as I know, it is complete ; that is, all the in- 

 dividuals of one sex differ from all the individ- 

 uals of the other. Such is the case in the Black- 

 bordered Yellow (Xanthidia Mcippe) [Fig. 155]. 

 In the male the black bordering band of the wing 

 is sharply defined and extends across the entire 

 outer margin. In the female the band is blurred 



