200 ANIMAL COLORATION. 



however, always limited to cases of this kind. Heliconias 

 belonging to different species or genera, often show such minute 

 resemblances as to suggest a mimicry ; and such facts, whidi 

 are numerous, do not appear at first to fit in with the theory 

 of mimicry. On the principle of utility it is easily intelligible 

 that an edible Leptalis would score a point or two in the battle 

 of life by being mistaken for an inedible Ithomia. But one 

 would have thought that the inedible and highly conspicuous 

 Heliconida3 might each have traded on their own peculiarities, 

 without needing a mutual resemblance in coloration. The 

 method is one whjch should perhaps have been treated of Iq 

 the chapter devoted to "Warning Colours"; but it is impossible 

 really, to draw a hard-and-fast line between these two classes 

 of phenomena. 



For instance, attention has been called to the fact that there 

 is a tendency among animals, which are believed to be pro- 

 tected by warning colours, to develop only a few patterns, and a 

 simple, sti'iking coloration. The larvas of the Fox moth, the 

 Cinnabar-moth, the adult wasp, and the wasp-like beetle 

 Clytus, agree in being marked with alternating rings of black 

 and yellow. Are we to call this mimicry ? 



It is believed that the simplification of the colours and 

 patterns is brought about to diminish the difficulties which 

 insect-eating animals must experience in distinguishing eatable 

 from uneatable insects. The fewer the patterns and colours, 

 the more easily will the lesson be learnt. The amount of 

 '' experimental tasting" will be reduced, and thus the insects 

 will profit. In the same way may perhaps be explained the 

 similarities among the Heliconidre. But there is another 

 explanation : it is certain that no form of protection — neither 

 resemblance to surroundings nor warning colours— is absolutel;/ 

 safe. (It is no objection to the theory that such colours have 



