7() " [September, 



the case of Curtisellus the majority were Curtisellus, but about one 

 in six were rustica. In both instances rustica was the earliest to 

 appear ; all the first specimens of both being rustica, all the last speci- 

 mens of both Curtisellus. 



Curtisellus, then, presents two distinct races — one living entirely 

 on bark, bud and leaves, usually of saplings ; a spring brood appears 

 the end of May (this year middle of June) which presents about one 

 in six of a dark brown or black form, usually with traces of the ordi- 

 nary marking. This has a summer brood, appearing in July and 

 August, the proportions of black specimens in which I cannot report. 



The other race (rustica) lives in the gall produced by mites on 

 ash trees ; the spring brood presents five dark specimens to one light, 

 but otherwise resembles the spring brood of the ordinary form ; its 

 summer brood is invariably black, and distinctly smaller than the 

 type. The hibernated larvae of the spring brood live on bark and 

 buds, similarly to the type, but less frequently attack the leaves, pre- 

 ferring the opening flowers, if too late to feed up in a bud. 



I failed entirely last autumn to find the mining larva? of Curtisellus. 

 I found rustica occasionally among the leaves, when failure of the 

 galls has forced him to shift for himself, and met with some very small 

 ones. These ate the lower surface from below, generally close against 

 a rib, and covei^ed themselves by a web passing from the rib to the 

 leaf, the resulting gallery being not unlike a mine. When a little 

 larger, it would fasten two leaves together flatly and live between 

 them. 



I may note that on several trees not only twigs but great branches 

 have died from the iittacks of rustica. They may have been weakened 

 by the larger call on the sap in growing the galls, but the real mischief 

 is done by the hibernating larva? injuring the bark of the twigs, and 

 especially devouring all the buds in spring. 



A minute Chalcis attacks the Diplosis, and two ichneumons affect 

 the Prays. Sundry omnivorous Tortrix larva? are found in the galls, 

 on which Eupithecia fraxinata feeds also. In the .spring very juvenile 

 larvae of C. xerampelina occur in the buds, and closely resemble those 

 of rustica, both in size and markings at that date. I also met with in a 

 twig of ash this spring a specimen (hibernating) of Hylesinus oleiperda, 

 which I never before succeeded in finding in this distinct, though some 

 twenty years ago I made rather active search for it. 



Firbank, Hereford : 



August, 1888. 



