290 CORRESPONDENCE OF COLOUR. 



ing.* Of the kind of imitation last mentioned we have noticed 

 several instances in the colouring of moths found commonly 

 on oak palings. We have one in our possession wherein not 

 only does the painting of the wings resemble the broader sur- 

 face of the wood, copied as accurately as by the most skilful 

 grainer; but even the transverse cutting at the pale's end 

 would seem to have served as a pattern for the striated cover- 

 ing of the insect's shoulders. 



It was supposed by Dr. Darwin that there is a general cor- 

 respondence in colour between butterflies and the flowers they 

 most frequent, and, theorist as he was, he concluded that such 

 resemblance was certainly designed as a protection from their 

 natural enemies; but, as well objected by a living naturalist, f 

 it is only when the insect is at rest, that this similarity of hue 

 with the object rested on (supposing its prevalence admitted) 

 can serve it for an illusory defence against birds, dragon-flies, 

 and other of its clear-sighted destroyers. The same protective 

 purpose has been assigned to the more singular resemblances 

 in form and coincidences of colour which we have just been 

 noting ; but such protection (if protection it be) is so partially 



* A common but very beautiful moth, called the Buff-ii/p (Pyg&ra bucephala), 

 displays a curious correspondence of colouring with the oak on which its caterpillar 

 most often feeds, and whereon, as a winged insect, it is frequently found resting. 

 The general hue of the wings is that purplish brown, mottled or powdered with sil- 

 very gray, so prevalent in the bark, especially of decayed oak-branches ; while the 

 buff-tip f eac h wing ( to which it owes its name) resembles exactly the end of such 

 a branch when obliquely truncated. 



t Kennie. 



