80 THE CASE OF PAPILIO POLYTES [ch. 



here than elsewhere on the island. All over Ceylon, 

 in fact, the relative proportions of the three forms of 

 female appear to be the same, quite irrespective of the 

 abundance or scarcity of either of the models. As, 

 however, we shall have to return to this point later, 

 we may leave it for the moment to consider other 

 features of this case of P. polytes. 



In collections of insects from India or Ceylon it is 

 not unusual to find specimens of the A form of female 

 of polytes placed with P. aristolochiae, and the H form 

 with P. hector. When the insects are old and faded 

 and pinned out on cork the mistake is a very natural 

 one. But after all the enemies of polytes do not hunt 

 it in corked cabinets, and any estimation of resemblance 

 to be of use to us must be based upon the living insects. 

 Are the resemblances of the mimics to the models when 

 alive so close that they might be expected to deceive 

 such enemies 1 as prey upon them and have no difficulty 

 in distinguishing the male form of polytes from P. aris- 

 tolochiae or P. hector ? 



To answer for a bird is a hazardous undertaking. 

 We know so little of the bird's perceptive faculties 

 whether of taste or sight. But on general grounds, 

 from the specialization of their visual apparatus, it 

 is probable that the sense of sight is keen, though 

 whether the colour sense is the same as our own is 

 doubtful 2 . On the other hand, the olfactory apparatus 



1 We shall take it for the present that, from the point of view of 

 mimicry, birds are the main enemies of butterflies (ef. Chap. IX). 



2 See later, p. 119. 



