RESEMBLANCES AMONG- ANIMALS. 73 



eaters are kept off by their bad odour and taste, but 

 are sufficiently invisible at night when it is of impor- 

 tance that their prey should not become aware of their 

 proximity. 



It seems probable that in some cases that which 

 would appear at first to be a source of danger to its 

 possessor may really be a means of protection. Many 

 showy and weak -fly ing butterflies have a very broad 

 expanse of wing, as in the brilliant blue Morphos of 

 Brazilian forests, and the large Eastern Papilios ; yet 

 these groups are tolerably plentiful. Now, specimens 

 of these butterflies are often captured with pierced and 

 broken wings, as if they had been seized by birds from 

 whom they had escaped ; but if the wings had been 

 much smaller in proportion to the body, it seems pro- 

 bable that the insect would be more frequently struck 

 or pierced in a vital part, and thus the increased ex- 

 panse of the wings may have been indirectly beneficial. 



In other cases the capacity of increase in a species is 

 so great that however many of the perfect insect may 

 be destroyed, there is always ample means for the con- 

 tinuance of the race. Many of the flesh flies, gnats, 

 ants, palm-tree weevils and locusts are in this cate- 

 gory. The whole family of Cetoniadas or rose chafers, 

 so full of gaily-coloured species, are probably saved 

 from attack by a combination of characters. They fly 

 very rapidly with a zigzag or waving course ; they hide 

 themselves the moment they alight, either in the corolla 

 of flowers, or in rotten wood, or in cracks and hollows 

 of trees, and they are generally encased in a very hard 



