VIII THE DISGUISES OF INSECTS 193 



escape would be much increased if it were surrounded by 

 real dry leaves instead of by green ones ; for if, when 

 pursued, it took shelter in a growing bush, it could hardly 

 fail to be still a conspicuous object. Marvellous to relate, 

 it does possess the habit of almost invariably entering a 

 bush loaded with dead leaves, and is so instantly lost to 

 sight, owing to its close resemblance to all the surrounding 

 objects, that I doubt if the most vigilant fly-catcher could 

 detect it. I have myself often been utterly puzzled. I 

 have watched it settle, apparently in a very conspicuous 

 situation, a few yards off, but on crawling carefully up to 

 the spot have been quite unable to detect any living thing. 

 Sometimes, while gazing intently, a butterfly would start 

 out from just before my eyes, and again enter another 

 dead bush a few yards off, again to be lost in the same 

 manner. Once or twice only was I able to detect it 

 sitting, and admire the wonderful disguise which a most 

 strange combination of colour, form, and habits enabled it 

 instantaneously to assume. But there is yet another 

 peculiarity which adds to the concealment of this species. 

 Scarcely two of the specimens are alike in colour on the 

 under side, but vary through all the shades of pale buff, 

 yellow, brown, and deep rusty orange which dried leaves 

 assume. Others are speckled over with little black dots 

 like mildewed leaves, or have clusters of spots or irregular 

 blotches, like the minute fungi that attack dead leaves ; 

 so that a dozen of these insects might settle on a perfectly 

 bare spray, and clothe it at once with withered foliage not 

 distinguishable from that of the surrounding branches ! 



The protection derived from a vegetable disguise is not 

 confined to the perfect Lepidoptera, but is often equally 

 remarkable in their larvae. The caterpillar of a European 

 moth that feeds on the privet {Hadena ligustri) is so 

 exactly the colour of the under side of the leaf, on which 

 it sits in the day-time, that you may have the leaf in your 

 hand and yet not discover it. In the caterpillars of the 

 Geometridse, form, colour, and habit combine to disguise 

 many of the species. Those of the Brimstone and Swallow- 

 tail moths may be taken as examples. They have the 



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