88 THE entomologist's kecord. 



repandata, etc. are capable of generalisation ; I may add that 

 B. rhoviboidaria var. perfwiiaria, DiiirncBa fagella, Hybernia 

 marginarid {progeinmarid), and other tree frequenting species 

 are excessively dark from the Huddersfield locality, and some 

 of the specimens of Cidaria ritssata are blacker from this localit}' 

 than from any other locality I know, except perhaps from the 

 neighbouring one of Sheffield. Arctia inendica has also under- 

 gone a remarkable change near Huddersfield, vide Trans. Ent. 

 Soc, pp. 441, 442, and PL xiv. (1889). 



I will cite one more example from our literature on this 

 subject. It is written by Mr. Edelston, and refers to AmpJii- 

 dasys brtiilaria. It is as follows : — " Some sixteen 3'ears ago, 

 the " Negro " aberration of this common species was almost 

 unknown. Last year I obtained the eggs of a female of the 

 common form, which had been crossed with a "Negro" male ; 

 the larvae I fed on willow, and had this year some remarkably 

 pretty aberrations, the connecting link between the " Negro " 

 and the usual form, but far before either as regards beauty. I 

 placed some of the virgin females in my garden, in order to 

 attract the males, and was not a little surprised to find that 

 most of the visitors were the " Negro " aberration ; if this goes 

 on for a few years, the original type of A. betiilaria will be 

 extinct in this locality " {Entomologist, vol. ii., p., 150, and Ent. 

 Mo. Mag., vol. xiii., p. 131). 



I will now quote a statement of Mr. Cooke {Entovi. x., 

 p. 151), which appears to me to illustrate the effect of damp- 

 ness due to woods on the development of dark forms of lepi- 

 doptera. Mr. Cooke says : — " Since my paper appeared, I 

 have bred two dark varieties of a light-coloured species from 

 the chalk. I never saw or heard of a dark specimen of the 

 species before last year, and it puzzles me to account for them, 

 as other dark specimens have been procured from the same 

 wood on the chalk. Had it not been so, I should have con- 

 cluded that the soot on my tree was the cause of aberration ; 

 but it is not so, for it is evident there is a dark race of this 

 particular species occurring on the chalk a long distance from 

 any manufacturing district." Just so, I can cite parallel cases 

 in Kent, but there is no doubt the wood is the cause of it ; the 

 dark race is more readily protected in the wood, where the 

 light race would be prominent, on the other hand, on the chalk 

 itself the white race would be protected ; hence, by " natural 

 selection," the darker wood variety would be perpetuated in 

 the wood, although the greater number of specimens, if it were 



