70 [March, 



takes the midrib for its base line, and occupies the whole of one 

 lateral half of an ordinary sized leaflet, a thick felt being spun across 

 the roof, which in consequence is thrown into unusually strong folds. 

 The mine of mespihlla also is fairly large and is governed in its 

 laying out by the midrib, but the folds of the roof are less conspicuous. 

 OxyacantJics makes a distinctly smaller mine than either of the others, 

 and being less under the control of the midrib its position and form 

 are more irregular. A mine in an apple leaf may also belong to one 

 of three species, concomitella, hlancardella or pyrivorella. I have never 

 myself met with the last named in apple, but Mr. Bankes who bred it 

 rather freely from this food-plant saw nothing to distinguish the mines 

 from those of the two other species, which in size, form and position 

 are exactly alike. Blancardella, however, feeds at a distinctly later 

 date than concomitella, and many of its larvse may be found still quite 

 young at the end of October. Taking advantage of this and of its 

 partiality for the wild rather than the cultivated plant, it is possible to 

 collect it almost unmixed with the commoner concomitella. The times 

 of their summer broods are still further apart — at any rate in 1895 1 

 bred absolutely pure broods of both. The mines of concomitella were 

 gathered early in June from hedge-row crabs, and produced the moths 

 (very small and pale) at the end of the month ; whilst July mines 

 from the same bushes produced hlancardella (small but full-coloured) 

 in August. Again, in the latter half of April, 1896, I sleeved some 

 bred hlancardella on an apple tree in the garden. Week after week 

 went by and nothing seemed to come of it ; so concluding the experi- 

 ment was a failure, early in July I used the same branch for a Tortrix. 

 Removing the muslin on August 5th to my surprise I found quite 

 a colony of LithocoUetis mines ; from some cause, however, there 

 had been great mortality among the larv^ when about half-grown, 

 and only two or three had managed to survive, and were then in 

 pupa. It is therefore pretty certain that the eggs, having resisted 

 for weeks the tropical heat, for which the summer of 1896 was so 

 remarkable, hatched somewhere about the end of June, and the com- 

 mencing mines would doubtless have been discovered at the time of 

 introducing the Tortrix, had I but given them a thought. 



THE MALE GENITAL APPENDAGES. 



At last we reach firm ground. In the evidence afforded by these 



parts, except in the case of ■pyrivorella, all room for doubt as to the 



rank of these insects vanishes ; they must be accepted as good and 



true species. The appendages are remarkable in two ways. Among 



