ii.] TYPES OF COLORING. 63 



tiger is the typical species, and which have stripes, 

 rendering them very difficult to see among the brown 

 grass which they frequent. It may, perhaps, be said 

 that this comparison fails, because the stripes of tigers 

 are perpendicular, while those of caterpillars are either 

 longitudinal or oblique. This, however, so far from 

 constituting a real difference, confirms the explanation ; 

 because in each case the direction of the lines follows 

 that of the foliage, The tiger, walking horizontally on 

 the ground, has transverse bars ; the caterpillar, clinging 

 to the grass in a vertical position, has longitudinal lines ; 

 while those which live on large- veined leaves have oblique 

 lines, like the oblique ribs of the leaves. 



It might, however, be suggested that the cases given 

 above are exceptional. I have, therefore, in a paper 

 read before the Entomological Society, tabulated all 

 our larger British caterpillars, and the result is very 

 interesting. As regards butterflies, we have sixty-six 

 species, out of which eighteen are spiny, and two may 

 fairly be called hairy. I do not speak of mere pubescence, 

 but of true hairs and spines. Now, out of these twenty, 

 ten are black, two greyish, six brown or brownish, one 

 greyish-green, and only one (L. sybilla) green. Thus, 

 while green is so preponderating a color among smooth- 

 skinned or ordinarily pubescent caterpillars (thirty- 

 seven out of the sixty-six species of butterflies being of 

 this color), only a single spiny species is thus colored. 



Now, let us look at these numbers under a different 

 aspect. Out of sixty-six species, ten are black ; and, as 

 we have already seen, all these are spiny or hairy. The 

 larva of Parnassius Apollo a species reputed to have 

 been taken in this country is stated to be black, and is 



