86 THE CAUSES WHICH PROPAGATE 



When we stroll or drive among those sequestered nooks in 

 Europe where Nature yet asserts her fairy reign, a little re- 

 flection shows us that with anthropods generally it is among 

 the sun-frequenting life that bright patterns occur; with others 

 haunting cooler shades, or active only during the low tempera- 

 tures of night, licheny or mossy designs are universal; and some 

 indeed are wholly black, bleached, or colourless, a feature yet 

 more marked in the subterranean hordes. Species that inhabit 

 the dark pools and streams, also, are dingy or dull as compared 

 with the wanderers of the air. Then if we consult a cabinet as 

 regards terrestrial climate, we shall further extend this law, and 

 find that the rays of the sun impart a richness of tint varying 

 with the ardour of his beams, and that tropical species which 

 are diurnal have a gaudiness compatible with the languor of 

 a clime that becomes their guardian, expressed in the opaque 

 jDaint-like pigment that imparts a varnish to their dermal tints, 

 with a heaviness to their external coverings. In the Brazils, 

 for example, all colours, whether of birds, insects, or flowers, 

 are brilliant in the extreme. Blue, violet, orange, scarlet, and 

 yellow are found in the richest profusion, and no pale faint 

 tints are to be seen. Even white seems purer, clearer, and 

 deeper than the white of other countries. Here, as elsewhere, 

 the butterfly kind takes precedence in regard to colour, and it is 

 also possible these colours are distributed as to district; for 

 example, metallic spots are very frequent on insects from the 

 Cape, a locality which also produces the well-known silver ti"ee. 



Protective colouring extends to the pupal and larval stages, 

 and markings exceptionally brilliant in caterpillars may effect gre- 

 gariousness, although sexual phenomena are here of course latent, 

 and the springs of action less comprehensible. The larvai and 

 nymphae of Manfidce, are, it is staled, sometimes coloured like 

 flowers for another object, that of attracting the insects on 

 which they prey, an end equally gained in the protective phyto- 

 mimicry of the imagines, which allows unsuspecting approach of 

 the victims. It is also affirmed that as a general rule cater- 

 pillars which are dull-coloured and have a smooth skin, or those 

 which are nocturnal in habits, are greedily eaten by birds ; and 

 on the other hand spiny and hairy Palmer-winms are spared and 

 often brightly coloured. 



