THE YOUNG NATURALIST. 



1S5 



the extent and manner of its variation, 

 illustrated with figures which give a better 

 idea than any number of words. Abraxas 

 grossulariata, the Gooseberry moth, is 

 represented in its normal form in Fig. jS. 



Fig. 38. 



The ground color of the wing is white. The 

 The base of the fore wing is orange, with 

 two rows of black spots, and there is an 

 orange band beyond the middle, also with a 

 row of black spots on each side of it. The 

 hind margin has also a row of similar black 

 spots, while others are dispersed is various j 

 parts of the wing. The hind wing has a 

 row of black spots at the hind margin and j 

 another across the middle, and as in the 

 forewings, various other spots in different 

 places. Now it will be observed that there 

 are but three colors, white, black, and 

 orange, and with these nearly all the 

 variations are produced. First, the black 

 and orange marking become fewer, until the 

 extreme form of the insect in this direction is 

 marked in Fig. 39 which is perfectly im- 



Fig. 39. 



maculate and retains but the faintest trace 

 of the orange basal patch and central band. 

 The black spots have even disappeared from 

 the body. This beautiful specimen is in 

 the rich collection of Mr. S. C. Gregson, 

 of Liverpool, who has, perhaps, the greatest 

 number, and grandest varieties of this in- 



sect ever gathered into one cabinet. He 

 has another equally clear of black marking, 

 but with the orange band as usual, and this 

 specimen has the veins and hind margin 

 tinged with the same hue. The second 

 style of variation is pre-shadowed by the in- 

 crease in the orange markings just named. 

 It is not easy to convey any idea of color in 

 a wood-cut, but the orange scales spread 

 over the whole of both wings, while the 

 usual band becomes of a much deeper hue. 

 We know of no specimen that is entirely 

 immaculate, and all suffused with orange, 

 the black spots being always present in 

 greater or less profusion, but so far as we 

 have seen, the tendency appears to be that 

 the deeper hues have most black, the paler 

 shades, fewer black spots. The third way 

 in which they vary is in the increase in the 

 number of black spots, in the general suf- 

 fusion of the wing with black scales, until 

 the extreme limit is reached in Fig. 40 



Fig. 40. 



which is not an uncommon form. Besides 

 these principal modes of variation there are 

 one or two others of rarer occurence. In 

 one of them the black spots, or other mark- 

 ings appear to be but thinly scaled, giving 

 them a leaden or transparent appearance ; a 

 spotted specimen of this variety looks al- 

 most as if it were greasy or semi-trans- 

 parent. Another more interesting change 

 appears to be a reversion to some older 

 form, for we get the smoky or lavender hue 

 of A idmata, about which we shall have 

 something to say on another occasion. 

 Sometimes the orange band becomes paler, 

 or yellower, but this may only be that the 

 colored scales are fewer, for when the 



