Striped Caterpillars 



Lord Avebury, who is a typical Wallaceian, 

 points out the connection that exists between 

 longitudinal stripes on caterpillars and the habit 

 of feeding either on grass or low-growing plants 

 among grass. The inference, of course, is that 

 birds mistake these caterpillars for leaves, or, at 

 any rate, fail to observe them when feeding, not 

 only because they are green in colour, but 

 because their longitudinal stripes look like the 

 parallel veins on the blades of grass. But the 

 butterflies of the family Satyrida^ as Beddard 

 points out, all possess striped larvae, and these 

 feed chiefly by night, when neither their colouring 

 nor marking is visible, while during the day 

 many of them lie up under stones ; other cater- 

 pillars of this family feed inside the stems of 

 plants. " Now," writes Beddard (Animal Coloura- 

 tion, p. 101), " in these cases the colour obviously 

 does not matter : if, therefore, the longitudinal 

 striping is kept up by constant selection on 

 account of its utility, and has no other significa- 

 tion, we might expect that in these two species 

 (Hipparc/iia semele and GEnis), and in others with 

 similar habits, the cessation of natural selection 

 would have permitted the high standard required 

 in the other cases to be lowered perhaps, even, 

 as has been suggested in the case of cave animals, 

 the colours being useless to their possessors, 

 might have disappeared altogether but they 

 have not." 



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