206 THK ENTOMOLOGIST. 



which takes the place of part of the nut, and in section show 

 white, har<], oviform or polyhedral inner galls, of about the 

 size of a hemp-seed. These are joined together with slightly 

 denser tissue, and in each there lies a gall-fly larva. Some- 

 times we find the acorn-shell only thickened by a single gall 

 at a place, but sometimes the seed is wholly appropriated, 

 and the whole acorn filled with these galls. Herr von Haim- 

 hoffen first observed some females from three-year old galls. 

 Of galls collected by me on September 28lh, 1869, I have 

 kept some quite dry, and others I have laid in water for a 

 tew hours from time to lime: those which I collected early 

 last autumn 1 have kept separate from those in sand, which 

 is kept moist. From none of these galls have I yet obtained 

 an insect, although in the greater part of them the larvae are 

 still living.— G. L. Mayr. 



This acorn-gall has rather puzzled me for some time. It is 

 doubtfully British. On October 26th, 1874, iMr. G. B. Rothera 

 wrote me that he had found an acorn-gall at OUerton 

 (Nottinghamshire) on September 28th, 1873, as follows: — 

 "My acorn-gall is certainly not that figured by Mayr, nor 

 does it agree with the description given by Giraud, which 

 applies to a multilocular gall. The one I found consisted of 

 a thin, shelly, unilocular gall, lying loosely within the acorn 

 case, and containing a large, fat, white, mandibulate 

 larva, closely resembling that of Cynips Kollari. Unfor- 

 tunately I damaged the larva in cutting open the gall, 

 so that there is no chance of hatching the insect. If the 

 larva had been a mere nomad, feeding upon the seed-lobes 

 (cotyledons), these would have shown the usual division ; 

 instead of this, however, we had a perfectly closed chamber, 

 with thin nut-like walls." In the early summer of 1875 Mr. 

 Cameron collected two or three galls in the neighbourhood of 

 Glasgow, which he referred to this species. These were from 

 the common oak ; and as the gall-maker has not been bred 

 they cannot be referred with certainty to the Quercus cerris 

 species. Mr. Cameron bred a specimen of Synergiis vulgaris 

 from one gall: this is given by Dr. Mayr as an inquiline in 

 the galls of A. glandium. On the other hand, last autumn, 

 guided by Miss Ormerod, I collected a quantity of the small 

 acorns of Quercus cerris var. Lucomhenua from Kew Gardens, 

 almost the whole of which were tenanted by larva3 : I at first 

 thought these might be coleopterous Balauiiri. A description 

 and note on these galls a])pears in the present issue (Kniom. 

 xi. 201): they somewliat difier from Mayr's figure, but like 



