KECOGA^ITIO^^ -MARKS 169 



Coloration for Concealment and for Visibility 



Colour and markings for concealment pervade all nature. 

 The hare on its form, the snipe in its covert, the vast major- 

 ity of birds while sitting on their nests, the sand-coloured des- 

 ert animals, and the prevalence of green colours in the in- 

 habitants of tropical forests, are a few of the best-known ex- 

 amples. The uses of such colours in order to protect the 

 Herbivora from enemies, or to conceal those which devour 

 other animals from their prey was at once acknowledged, and 

 it was seen how, with variability of colour as a constant fact, 

 survival of the fittest might soon bring about the beautiful 

 harmony of coloration we everywhere find to prevail. But it 

 was also undeniable that there were almost equal numbers 

 of animals of all classes and sizes, in which colours and mark- 

 ings occurred which could not by any possibility be interpreted 

 as protective, because they seemed to render the creature 

 glaringly conspicuous. Some of these, which w^ere most prev- 

 alent among insects, were soon explained as " warning 

 colours,' ' because they were exhibited by species which were 

 either so nauseous as to be inedible by most insect-eaters ; or 

 were armed wdth stings which might cause great pain or even 

 loss of life to an enemy which attacked them. When it was 

 found that many other groups of insects which did not pos- 

 sess these protective qualities, yet acquired the same colours 

 and often the same form ; and when my fellow-traveller on 

 the Amazon, II. W. Bates, showed how this peculiar kind of 

 ^^ mimicry " was beautifully explained on the Danvinian 

 hypothesis, not only w^as the theory itself greatly strengthened 

 but a whole host of curious and beautiful colour-phenomena 

 in Xature, hitherto unnoticed, were seen to come under some 

 form of the same general principle. As one rather extreme ex- 

 ample of mimicry I give the figures of a black wasp with white- 

 banded wings, which is closely imitated by a heteromcrous 

 beetle. These I captured myself in the forests of Borneo, fly- 

 ing together near the ground. They are of nearly the same 



