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then seen, I think) were C0mpfa-Vike forms of D. nana. 

 Further, both were convinced that if the specimens recorded 

 as British were really compta, then the said specimens were 

 undoubtedly Continental and not British examples. In the 

 teeth of this there are people who believe in British compta^ 

 and I am one of them. 



In Central and Southern Europe D. compta is commoner 

 and more generally distributed than D. nana ; but the latter 

 has a far more northern range where it becomes melanic. In 

 the most northern and some of the eastern localities in which 

 D. compta occurs, it also has a melanic form. Throughout 

 the common area of the insect's distribution, forms of nana are 

 hardly, if at all, separable from compta, and dark forms of the 

 latter from melanic forms of nana. The larva of compta is 

 said to be different from that of nana. It feeds on pinks and 

 also on Silene. In nature the larva of nana has only been 

 found on Silene ; but it will also eat the unripe seeds not 

 only of pinks but also of sweetvvilliams in confinement, as I 

 have had frequent opportunities of proving. If my memory 

 serves me, the larva of nana, when feeding on sweetwilliam 

 or pink, is somewhat different in appearance than when 

 feeding on Silene. As the pale forms of nana are connected 

 by intermediates with the melanic forms, so also are they 

 with compta ; and I am inclined to think that both compta 

 and nana are forms of a primordial species represented in the 

 present day by the melanic specimens of nana. 



The larva of nana has continued attached to Silene, whilst 

 the larva of compta has seized on Dianthus, hence probably 

 the difference in colour and marking of the two larvae. It 

 may be mentioned that plants of the tribe Silene have a more 

 northern distribution than plants of the Dianthus tribe : both 

 genera belong to Caryophylleae. 



In conclusion I must briefly refer to the variation of D. nana. 

 Taking Stainton's description we have for the type an insect 

 whose primaries are " dark grey, with pure white markings ; 

 the orbicular stigma and a blotch below it white ; the reni- 

 form stigma pale grey ; the lines whitish, margined with 

 dark grey ; a whitish dash along the inner margin." From 

 this type there is aberration in two very opposite directions. 

 On the one hand, the dark grey gradually gives way in favour 



