NOCTU^E. 247 



\YE now come to one of the largest groups of 

 British Moths, the NOCTU^, so called because, as a 

 rule, they are exclusively night-fliers, and never, except 

 by accident, appear in the day-time. In these Moths 

 the body is almost always stout and thick, as is the 

 thorax, the hairs of which often rise nearly erect, so as 

 to form a sort of crest. Generally these Moths hide 

 themselves by day, taking advantage of crevices in 

 walls, the bark of trees, old posts, palings, and invari- 

 ably selecting those which best harmonise with the 

 colour of their closed wings. So close is often the 

 resemblance between the colour of the insect and that 

 of the object on which it rests, that even the most 

 experienced and keenest entomologists often find 

 themselves deceived, and have only detected the well- 

 disguised insect when, by an accidental touch, they 

 have forced it to take flight. Even those species 

 which have their under_ wings adorned with beautiful 

 colours, have almost invariably their upper wings 

 plainly mottled with brown, grey, black, and dun, so 

 that when they are at rest the splendid under wings 

 are concealed, and their glories veiled by the sombrely 

 tinted upper pair. Many, in fact, most of them, have 

 both pairs of wings coloured in the simplest and least 

 imposing manner, not even having any bold black, 

 white, or brown markings on either pair of wings. 

 Consequently, when a number of Noctuae, which are 

 of about the same size, are collected, it is a very diffi- 

 cult matter to refer them to their proper positions, and 

 even the most skilful of entomologists is forced to refer 

 to his books before he can, with any confidence, assign 

 to some sixty or a hundred Noctuse their exact names. 



