vii DEFENCES OF INSECTS 261 



finches, chaffinches, and other birds of the kind. It is 

 thus proved to be unpalatable to them, and we may 

 conclude that it is exempt from all attack, which 

 appears very likely because of its great abundance 

 and its conspicuous white colour. The moth Dia- 

 phora occurs about the same time of year, and the 

 female alone is white. It is much like Spilosoma, 

 and might easily be mistaken for it in the dusk, while 

 the male is dark, and protectively coloured, so that 

 this species is probably palatable ; it is also much less 

 common. All the facts point to the female Diaphora 



FIG. 54. The larva of Puss Moth (Centra vinnla) resting ; full fed ; natural size. 



being a mimic of Spilosoma, standing in the same 

 relation to it as their mimics do to Heliconidae and 

 Danaidae. Until the palatability of the supposed 

 mimic is proved, however, this cannot be definitely 

 advanced as an instance of true Mimicry, and must 

 be classed among the close resemblances between 

 unpalatable forms protected by Warning Colours. 

 The affinity between the two species will likewise 

 always exclude it from the best examples of mimicry, 

 When studying mimetic resemblances among but- 

 terflies, the conclusion is forced upon us that the 



