1892.] 



THE BRITISH NATURALIST. 



195 



matter most fully, and it is not only absolutely certain that there are 

 two broods of the butterfly every year, but it is the easiest thing in 

 the world to separate the broods, as well as the sexes, from an 

 examination of the perfect insects only. If anyone with a tolerably 

 good series of the species will take the trouble to examine the under- 

 sides of the wings, they will find four distinct types of marking and 

 colouration. The first is dull dark brown, almost without markings ; 

 the second is of the same colour, but is richly varied with different 

 shades of brown and green, the latter colour being most prevalent 

 towards the hind margin of the wings ; the third may be called 

 fulvous yellow, with very slight markings, but not so uniform as the 

 first form ; whilst the fourth is also fulvous yellow, but much varied 

 with other shades of yellowy pale brown, and green. The four forms 

 are so distinct that if only one of them be exammed, it may be said 

 with certainty to which it belongs. The commonest form is that with 

 brown underside, and it is produced from the larvae found so abun- 

 dantly in some years by the hop-pickers. The butterfly emerges late 

 in September, in October, and I have had it emerge in November. 

 These hybernate, re-appear in the Spring, and lay their eggs on 

 currant or nettle, producing the early summer brood, the undersides 

 of which are of the fulvous yellow^ forms described above. In both 

 broods, those with plain, almost uniformly coloured undersides are the 

 females, and those much mottled and varied are the males. Perhaps 

 the following will make it quite clear : 



Early ( Underside : | Few Markings. — Female. 

 Sunimer - Fulvous- 

 Brood. ( yellow. I Much Varied. — Male. 



Autumn \ Underside : 1 Few Markings. — Female. 

 Brood. { Dull Brown. ^ ]Much Varied.---Male. 



As the autumn brood hybernates, it is quite possible to capture 

 pecimens with brown undersides almost simultaneously with the 

 arlier specimens oi those having yellow undersides^ which are their 

 irect progeny, but such examples will be too much worn for any 

 oubt to arise. I have referred, so far, to the undefsides, and they 

 re by far the best guide for separating the broods and sexes. If, 

 however, a series of these butterflies be arranged in this manner, it 

 will be found that the early summer brood are perceptibly paler in hue 

 than those of the autumn brood. I would not say that every 

 specimen could be placed m its correct position by an examination of 

 the upper side, but the difference is clear enougli when they are once 

 correctly placed. It is said, that if a lie has twenty minutes start, it 

 will travel all round the world before it can be overtaken. So of a 

 scientiflc error. Though I fully explained all this in the "Young 

 Naturalist," Vol, 11., pp. 108-110; and though the facts are correctly 



