64 ON PLANTS AND INSECTS. [lect. 



at least are still of that colour when first born. Then 

 there are the spotted or eyed cats, such as the leopard, 

 which live among trees ; and their peculiar colouring 

 renders them less conspicuous by simulating spots of 

 light which penetrate through foliage. So also many 

 caterpillars are marked with spots, eyes, or patches of 

 colour. Lastly, there are the jungle cats, of which the 

 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 1 British caterpillars, and the result is very interest- 

 ing. 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 colour among smooth- 

 skinned or ordinarily pubescent caterpillars (thirty-seven 



