222 A NATURALIST IN BORNEO 



coloured butterflies are preserved by cryptic habits, so 

 is it absurd to suppose that all brightly coloured butter- 

 flies are protected by nauseous properties. They can 

 be equally well protected by habits of wariness, rapid 

 dodging flight, and great fertility. The Pierince are 

 for the most part very conspicuous butterflies, but 

 there are no grounds for supposing that any but a 

 few genera are distasteful ; in fact, Mr. Marshall has 

 shown that few sub-families are more preyed on by 

 birds. White or yellow with black tips to the wings 

 is the common type of colouring in this sub-family, and 

 to allege as has been alleged that certain species so 

 coloured mimic other similarly coloured species of the 

 same sub-family, is about as sensible as to allege that 

 every blue Lycaenid is a mimic of or a model to every 

 other blue Lycaenid ; in fact, if we will only recognize 

 that the mimetic theory is not capable of universal 

 application, if we will regard warning, cryptic, and 

 mimetic colouring as only three factors amongst many 

 others which help to ensure safety to insects, we shall 

 gain a saner view of insect life, and perhaps thereby 

 pacify our opponents. 



I do not see why such scorn should be heaped on 

 cases of imperfect or incipient mimicry. Apart from 

 the fact that when we place side by side in an insect 

 cabinet a mimic and its model, we submit the mimic 

 to a test far more severe than any to which it is 

 called upon to undergo in the field, we must re- 

 member that natural selection is operating to-day as 

 in the past, and surely it is reasonable to suppose that 

 if in the past this force has produced well-nigh perfect 

 mimics out of imperfect, then it can do so now. 

 Moreover, it may be argued that many an imperfect 



