48 [February, 1894. 



instead of a single turn back upon itself, two or three are made, if the 

 leaf be small and thin, yet for all that the mine is so small that it 

 manages to keep within the limits of the lobe. The other position 

 for the egg is under one of the ribs. In this case the small twisting 

 gallery keeps within a narrow compass in the middle of the leaf or in 

 one of the lobes. To compare it now with oxyacanthella. 



The eggs of both are laid upon the under-side, but whilst gratio- 

 sella prefers the stalk to a rib, oxyacanthella has a greater liking for 

 the ribs. The mines are very similar. But gratiosella% is smaller 

 and its course more timid, the gyrations being short and keeping close 

 together ; whereas in oxyacanthella the curves are sweeping and pass 

 across or round the lobes from one side of the leaf to the other, and 

 even when the egg is laid upon the stalk and the mine comes out along 

 the edge as in gratiosella, it turns off sooner or later into the body of 

 the leaf and pursues its usual bold and wandering course. The best 

 distinction, however, lies in the larvae. The head of gratiosella is of 

 the palest brown, so that little more than the mouth-parts are visible 

 in the mine ; that of oxyacanthella is grey or black, and is always 

 distinct and sometimes \qvj distinct ; oxyacanthella also shows, but 

 obscurely, the cephalic ganglia, of which there is no trace in the other. 

 I think, too, that the ground-colour is more bluish in gratiosella than 

 in oxyacanthella, but never having had the two side by side I speak 

 doubtfully. In these parts, and I am fairly well south, both species 

 are single brooded. I never find the larva of oxyacanthella in July 

 and August, nor that of gratiosella in September and October, and I 

 have given the hawthorn hedges a good deal of attention. 



The blotch-miners, regiella and ignobilella. They occur together 

 at about the same time, and are double brooded, feeding in the summer 

 and again late in the autumn. The small blotches they make at the 

 tips of the lobes, with their yellow or yellowish larvae, are certainly 

 most provokingly similar, unless attention be paid to one or more of the 

 following points, when their discrimination becomes as easy and 

 pleasant as it before seemed impracticable. In both the egg is laid 

 on the under-side, in regiella quite on the edge, in ig7iohilella well 

 away from it. As a consequence, the whole course of the primary 

 gallery of the former runs along the edge, whereas the gallery of the 

 latter wanders at first about the area of the lobe before it reaches and 

 follows the edge, and though this wandering portion is afterwards 

 absorbed by the blotch, the fine frass track remains undisturbed and 

 an evidence of its former existence. Next, regiella deposits brown 

 frass in its gallery and black in the blotch, whereas the dejecta of 



