316 BRITiStl LEPibOKfERA. 



specimens of one species to the other, had I not been guided by the 

 information furnished by the larvre (Heinemann). Stainton says: 

 " N. mjjrtillella is most nearly related so N. salicis, but the fascia is 

 more slender and brighter than in that species." Heinemann refers 

 N.fcujdla, H.-Sch. (= N.facji, Frey) also to this species (vide., Zool., 

 xxi., p. 8384), but Frey supposed his N. fayi might be a small summer 

 brood of N. carpinella (Lep. iter Schwelz, p. 425). 



Egg-laying. — The egg is laid on the underside of a leaf of 

 Vacciniwn, either on, or very close to, the midrib (Stainton); some- 

 times on the margin of a leaf (Nolcken). 



Mine. — The mine is at first much contorted, and of a reddish 

 tinge, the excrement forming a rather broad, irregularly waved black 

 line ; when the larva is about half-grown, the mine becomes more 

 blotched, the excrement only occupying a small area. Some mines 

 are said to run along the edge of a leaf, going in and out the serra- 

 tions (Stainton). Heinemann says " the mine is serpentine, unless 

 the confined space compels a blotch-like formation." Nolcken notes 

 the mine as being " sometimes placed near the margin, the larva 

 extending its mine therefrom until it occupies the entire half of a leaf ; 

 in other cases the mine is commenced near the midrib, and spreads 

 to the margin. The first part of the mine is narrow (scarcely wider 

 than the body of the larva), then it increases from five to ten times its 

 original width, the windings still, however, remaining close together ; 

 finally the larva eats away the partitions between the convolutions, 

 and converts the gallery into a large irregular blotch. The frass is 

 arranged in little heaps, forming a broken line, in the first part of the 

 mine ; in the second part the heaps are larger, but the frass always 

 occupies comparatively little space, the greater part of the gallery 

 being represented by the pale excavated portions of the mine." 



Larva. — Length 2 lines. Amber-yellow in colour ; head pale 

 brown, the mouth and two receding hinder lobes darker brown 

 (Stainton). Nolcken describes it as "paler or darker yellow, with 

 transparent, pale-brownish head, the mouth and sutures darker broAvn ; 

 the yellowish-grey (or brownish) dorsal vessel indistinctly seen on 

 back ; a series of brown lozenge-spots on venter, the hinder ones 

 longer and more sharply pointed." Wood notes it as mining with 

 the dorsum uppermost. 



Cocoon. — The cocoons (7) average 3 mm. in length, and 1-8 mm. 

 in width, forming, roughly, a long oval in outline, and with but little 

 difference in the size of the ends. The cocoons are spun on the upper 

 side of a Vacciniwn leaf, and have accommodated themselves to the 

 surface, sometimes showing a rather broad flange where there has been 

 a fold in the leaf. The upper portion is well arched, the apex being 

 almost central, but the cocoons appear to be thin, and to collapse 

 irregularly in some places. They are uniformly yellow-ochreous in 

 colour, inclining to orange, the main structure moderately smooth, but 

 with a considerable amount of adherent pale, flossy, silken fibres all 

 over it, although these are more abundant round the rim than else- 

 where. The empty pupa-case projects below the rim ; it is absolutely 

 transparent and colourless, without any trace of shading, and extremely 

 delicate. [Described under a two-thirds lens, June 28th, 1898, from 

 cocoons sent by Mr. W. H. B. Fletcher.] Heinemann notes it as 

 " broad and flat, rather long, and brown." Nolcken says " it is gene- 

 rally brownish-yellow, but both the colour and shape are very variable." 



