1894.1 47 



one or more of the foregoing characters. Let me take first four 

 species that feed on hawthorn {Gratcegus oxyacantlia) . They divide 

 themselves naturally into pairs, the one characterized by having bright 

 green larvse and gallery mines with coiled frass, and the other by 

 yellow or yellowish larvae and blotch mines. 



The gallery miners are gratiosella and oxyacantJiella. With regard 

 to the former the ground wants a little clearing first. Some years 

 ago, in the pages of this Magazine, Mr. Threlfall suggested that 

 gratiosella and ignohilella were the sexes of one and the same species. 

 Subsequently, my own experience in breeding ignohilella appeared to 

 confirm his view. From yellow larvse collected in the autumn and 

 carefully separated from the only two other yellow larvse, viz., regiella 

 and pygmcBella, that could be found on the hawthorn {gratiosella, let 

 it be remembered, was said to have a yellow larva and to feed in the 

 autumn), I bred a long series of the perfect insect, some with red 

 heads and some with black ; as the former were all males and the 

 latter females, they could clearly be nothing more than the sexes of 

 one species, and gratiosella as a species seemed doomed. It was not, 

 then, till the question arose what the green oxyacanthella-\\kQ larvse, 

 feeding in .Tuly and August, could be, and until moths were reared 

 from them which answered accurately to the description of gratiosella, 

 that its position was restored. The diagnosis in the " Manual " is 

 perfect, so far as the imago goes. It is a smaller insect than ignohilella, 

 with the head black in both sexes, and a violet rather than a purple 

 hind margin to the fore-wings : on the other hand, the larva is bright 

 green, not yellow as there described, and instead of feeding in Sep- 

 tember and October, as stated in the " Entomologist's Companion," is 

 fed up and over by the end of August. 



The general cut of its mine varies according as to where the egg 

 is laid, and to some extent according to the size and fleshiness of the 

 leaf. The favourite spot for the egg is underneath the leafy frill 

 edging the stalk. The mine travels at first for a short distance down 

 the stalk, I mean in the direction of the trunk, it then turns round 

 and proceeds in the opposite direction till it reaches the blade, here it 

 keeps accurately to the edge for some little way, and then makes one 

 short turn back upon itself and ends, or, if the leaf be especially large 

 and fleshy, the last turn is omitted. This form w^ould be quite sui 

 generis, were it not occasionally mimicked to a turn by pygmceella ; 

 still, as the one larva is green and the other yellow, there is no risk 

 of confusing the full mines, whilst the empty ones, as I have already 

 pointed out, may be told from the position of the eggs. Sometimes, 



