250 ANIMAL COLORATION. 



of the phenomena would have to be sought for. The theory is 



j */ 



mainly supported by instances among Lepidoptera, which is, 

 no doubt, due to the fact that it was in this group that the 

 phenomena were first studied. From certain points of view it 

 is unfortunate for the theory that this is the case: Lepidoptera 

 are, as a rule, very short-lived in the imago state. 



If cases of undoubted mimicry could be shown to be more 

 numerous among the higher and longer-lived animals than they 

 have yet been, they would furnish much stronger evidence for 

 the truth of the theory. A mammal which may have to exist 

 for some years before it can reproduce its kind needs protection 

 much more than an insect, which sometimes pairs the moment 

 it leaves the cocoon. There are even cases on record of male 

 moths waiting by the unopened cocoon in expectation of the 

 emergence of the female. 



Relative Unimportance of the Imago Stage in Butterflies. 



It may seem paradoxical to say that the perfect butterfly, 

 which has passed through so many preparatory stages, is the 

 least important stage of all. In a certain sense also it would 

 be manifestly untrue, for the butterfly lays the eggs, and upon 

 the life of one female insect depends the future existence of 

 perhaps a large number of butterflies. There is no doubt that 

 a single butterfly deposits, under favourable circumstances, a 

 great cjuantity of eggs, from two to five hundred, according to 

 the species, is one estimate, but it is also calculated that out 

 of these eggs only 1 per cent, reach maturity : if that is so, 

 the life of an average female butterfly is only worth three or 

 four times that of a caterpillar. 



As long as the perfect insect is able to pair and lay its eggs, 

 that is all that is necessary after this its life is of no value ; 

 and it is immaterial whether it is destroyed or lives on for a 



