290 CORRESPONDENCE OF COLOUR . 



resting.* 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 surface 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 covering 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 \vas certainly designed as a protection from their 

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

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

 witli 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-tip (Pygara lucepJtala), 

 displays a cm-ions correspondence of colouring with the oak on which its cater- 

 pillar 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 silvery grey, so prevalent in the bark, especially of decayed oak- 

 branches ; while the buff-tip of each wing (to which it owes its name) resembles 

 exactly the end of such a branch when obliquely truncated. 



f Renuie. 



