BUTTERFLIES 69 



attack, The odour of this substance is so penetra- 

 ting that it taints and renders useless everything it 

 touches or in its vicinity. Provisions near it 

 become uneatable, and clothes saturated with it will 

 retain the smell for several weeks even though 

 repeatedly washed and dried. A drop of the liquid 

 in the eyes will cause blindness, and Indians 

 are said sometimes to lose their sight from this 

 cause. Owing to this remarkable power of offence 

 the skunk is rarely attacked by other animals, and 

 its black and white fur and the bushy white tail 

 carried erect when disturbed, form the danger 

 signals by which it is easily distinguished in the 

 twilight or moonlight from unprotected animals. 

 Its consciousness that it needs only to be seen to 

 be avoided gives it that slowness of motion and 

 fearlessness of aspect which are, as we shall see, 

 characteristic of most creatures so protected." 



Recognition Colours. A good instance of this 

 class of colouring is seen in the upturned white tail 

 of the rabbit which, although making it conspicuous 

 to its enemies as well as friends, is probably a 

 signal of danger to other rabbits ; and when feed- 

 ing together, in accordance with their social habits, 

 soon after sunset or on moonlight nights, the 

 upturned tails of those in front serve as guides to 

 those behind to run home on the appearance of an 

 enemy. Many birds, antelopes, and other animals 

 have markings believed to serve a similar purpose, 

 and probably the principle of distinctive colouring 

 for recognition has something to do with the great 

 diversity of colour met with in butterflies. 



