PROTECTIVE MIMICRY 241 



resemblance between unpalatable forms, described 

 under Warning Colours (see pp. 191-96). The close 

 affinity between the two species, and their similarity 

 to other closely related species, probably indicate that 

 the resemblance is due to arrested divergence rather 

 than convergence ; if so, the case before us is not a 

 good and typical example of Mimicry. 



A similar objection holds against an example in 

 which I have experimentally proved that the benefits 

 of true Protective Mimicry are certainly conferred. I 

 refer to the unpalatable and abundant white Satin 

 Moth (Stilpnotia salicis), which is resembled by its 

 near relative, the common white Gold Tail Moth 

 (Porthesia auriflud). The abundance of the latter, 

 and the affinity between the two species, make this 

 instance a very bad one, but the experiments were most 

 instructive, and indicate the benefits derived from 

 Mimicry in a most suggestive manner. 



Experimental evidence of the protection afforded by 

 mimetic resemblance 



I offered a Satin Moth to a marmoset which was 

 excessively fond of insects, and which had not gratified 

 this appetite for some days. He seized the moth, and 

 ate it with the strongest expressions of disgust, well 

 known to all who are acquainted with him ; in fact, 

 had not the attempt been made to take the moth 

 away, I believe that he would have rejected it. As 



