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THE WOKLD OF LIFE 



like their mates as possible, are able to recognise each other. 

 Intuitive knowledge or " instinct " is now given up by every 

 thinker; but the proof now given that the only knoiun method 

 of mutual recognition by Lepidoptera is by scent, explains the 

 whole difficulty. The colours and markings of these insects 

 have been produced in adaptive relation to their enemies al- 

 most exclusively, and this explains the fact that the strangely 

 diverse females above referred to are, probably in every case, 

 either protectively coloured or mimics of distasteful forms 

 in their own district. The fact that several of the Eastern 

 Papilios have fully tailed females while they themselves are 

 round-winged, is another indication that sight can have no 

 part in leading to mutual recognition between the sexes. 



The almost universal presence of some form of recognition- 

 marks in birds and mammals, no less than the proof now af- 

 forded (and for the first time stated) of their entire absence in 

 the Lepidoptera, affords, I think, ample justification for the 

 importance I claim for them, and for the space I have devoted 

 to them in the present volume. 



