Insect Camouflage. 139 



noses against it, only to discover its whereabouts when it again takes 

 flight. True, its underside is of a dark colour and largely protective, but 

 its escape is probably more often due to the sudden disappearing trick 

 rather than to the colour of its underside, though the two combine to 

 form a remarkable degree of protection. 



Another example, and one that is common on the coastlands, is the 

 Arctiid moth Utethesia omatrix L., the larvae of which feed on the 

 common weed Crotolaria retusa, known locally as ' rattle bush.' This 

 moth when at rest is quite inconspicuous, the upper surface of its wings 

 being pale pinkish yellow. When this insect is disturbed and takes flight 

 it can easily be followed by the bright red of the underside of its fore- 

 wings ; it alights suddenly, with a sort of headlong pitch, and is then 

 quite hard to find. 



As already pointed out, it is in a somewhat similar way that the 

 camouflage of ships was carried out, the object being not inconspicuous- 

 ness but dazzling effect. 



Directive Coloration. — This leads us to another kind of colora- 

 tion — directive coloration. Here the object is to focus the attention of 

 the other animal on a certain part of the insect, and in that way divert 

 its energies from more vital parts. In a general way ' flash colours ' 

 could be included under this head. 



In this, as in other subjects of natural history, it will often 

 be found almost impossible to make any distinct divisions between 

 the different methods of camouflage, for if looked at from one point of 

 view they will come under a certain head, while from another they are 

 very different. 



In certain butterflies we observe peculiar markings called 'eye-spots.' 

 Eye-spots are areas which are invariably very conspicuous and which 

 are usually remote from the head, resembling in a general way larce 

 eyes. They are usually large enough to belong to an animal many times 

 the size of the one exhibiting them. Their effect is generally supposed 

 to be ' terrifying.' Here again we find an overlapping — directive and 

 terrifying coloration. 



A good example of such ' eye-spots ' is to be found on the under- 

 wings of our Caligo illioneus illioneus L., the larvae of which feed on the 

 sugar cane. 



Warning Coloration. — Although this is seldom used in its re- 

 stricted sense as a camouflage it is so employed in mimicry, and as it is 

 the intermediate step between directive coloration and mimicry it will be 

 as well to consider it here. Warning coloration is only a variation of 

 directive coloration in which the colour-scheme is associated with some 

 unpleasant character which the insect possesses, such as a sting, irritating 

 hairs, unpleasant taste, or offensive odour. 



