2O6 



ENTOMOLOGY 

 FIG. 234. 



FIG. 235. 



Pieris protodice ; male (on the left) and female (on the right). Natural size. 



are often distinguished by colorational differences and in Hes- 

 periidse the males /often have an oblique black dash across the 

 middle of each front wing. Callosamia promethea (Fig. 

 236), the gypsy moth and many other Lepidoptera exhibit 

 colorational antigeny. In not a few Sesiidse the sexes differ 



greatly in coloration. Thus in the 

 male of the peach tree borer (San- 

 ninoidea exitiosa) all the wings are 

 colorless and transparent; while in 

 the female the front wings are vio- 

 let and opaque and the fourth ab- 

 dominal segment is orange above. 

 The same sex may present two 

 types of coloration, as do males of 

 Cyaniris pseudargiolus and females 

 of Papilio glaucus, already men- 

 tioned. Papilio merope, of South 

 Africa, is remarkable in having three 

 females (Frontispiece, Figs. 5, 7, 9, 

 if) which are entirely different in 

 coloration from one another and 

 from the male. There is no longer any doubt, it may be 

 added, as to the specific identity of these forms. 



Next to Lepidoptera, Odonata most frequently show col- 

 orational antigeny. The male of Calopteryx maculata is vel- 



Colias philodice; right fore 

 wing of male (above) and of 

 female (below). Natural size. 



