March, 1894. ! 49 



ignobilella are black in both gallery and blotcb. Lastly, the head of 

 regiella is pale brown, with the cephalic ganglia dark brown, and con- 

 sequently far more conspicuous than the head ; on the other hand, 

 the head of ignobilella is blackish, overpowering the ganglia, which 

 are of a paler colour. I should add that a pair of brilliant orange 

 spots are frequently present on the front edge of the 2nd segment in 

 regiella. I was inclined at one time to think that they might be a 

 sexual distinction, but careful breeding lent no support to the idea. 

 Thus, these species are distinguished by four distinct characters, 

 gathered from egg, mine, frass (colour), and larva. All four are 

 practically of much the same value, for all are equally constant and 

 equally accessible to observation. 



With regard to the pupation of these several insects. Oratiosella 

 is subterranean, and makes a smooth blackish-brown cocoon. Oxyacan- 

 thella and regiella spin on (below ?) the surface or above it, the former 

 will sometimes climb up the sides of a glass vessel to pupate ; both 

 make smooth cocoons, oxyacanthella of a dark brown, regiella more of 

 the colour of a|dogskin glove. I have no cocoons of ignobilella to refer 

 to, and have also forgotten to make any note of their appearance. 



Titgrella and fulgens, the Nepticul^ of the beech (^Fagus sglvafica), 

 require perhaps a word. The mines might be fairly well sorted by 

 their size, the smaller ones being referred to Titgrella, and the larger 

 to fulgens ; but in any large number there would always be some spe- 

 cimens that held an intermediate position, and could not be referred 

 confidently to either division. Size alone is, therefore, not sufficient ; 

 neither is the form of their track, for though the mine of the former 

 is a vermiform gallery confined to the space between two ribs, and that 

 of the latter a more or less straight gallery which pays little regard to 

 boundaries, yet sooner or later we should be landed in difficulties, 

 since either wall on occasion adopt the pattern of the other. Fortu- 

 nately more trustworthy distinctions exist, and under no less than 

 three heads, viz., egg, mine, and larva. (1) Egg — in titgrella they are 

 laid on the under-side, among the tufts of hair that grow in the angles 

 of the midrib — a most excellent example, I may add, of the precision 

 which some of the species display ; fulgens, on the contrary, is one of 

 the rare instances of utter indifference in the matter, and lays on the 

 open surface of upper- or under-side equally readily. (2) Mine — 

 the great point here is the piece of " coiling " in the middle, which is 

 always present in fulgens, and as invariably absent in Titgrella. (3) 

 Larva — the head of THyrella is black, especially its posterior lobes, the 

 cephalic ganglia also black and looking like a part of the head, ventral 



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