368 



FOREST ENTOMOLOGY, 



July to September. When fully ripe it fulls to the ground, where 

 the larvae pupate, and the flies emerge the following spring. I have 

 found it in Alnwick parks, but it is not so conspicuous on the leaves 

 as G. jdli[ier. 



ASPHOXDYLIA SAROTHAMNI, Lw. 



This insect is important from a collector's point of view, but may 

 easily be overlooked, as the galls formed by the larvae, very much 

 resemble the unopened flower-buds (fig. 340). They are larger in 

 size, and comparatively hard in the outer struc- 

 ture, being lined with a greyish pubescence, and 

 containing a single larva. The metamorphosis 

 takes place within the gall. 



The flies (fig. 341) hatch out from the begin- 

 ning to the end of June, and in order to follow 

 out the development they may be looked for about 

 the first of May, as they are then in the larval 

 stage. The pupal stage is comparatively short. 



As compared with the Cecidomyia, the flies 

 are very much larger, and the venation of the 

 wings more distinct. Body dark-grey, head dark, 

 and wings brown and hairy. Antennae of female 

 13- or 14 -jointed, the three joints at the tip 

 being very small in size. 



Fig. 342 is a photograph of the pupal form. 



Lasioptera rubi, Heeg. 



Fig. 340.— 'j'a^^s on hroom 

 caused by Asphondylia 

 sarothamni. 



The larvae of this insect cause galls on the 

 stems of the common bramble (Rubus fruficosus) 

 (fig. 343), and it is of course more interesting as an entomological 

 specimen than a forest insect. I have oidy twice found it — once in 

 Cheshire, and very plentifully near Ville la Villiers, Belgium. It 

 is, however, said to be very common in some parts of the south of 

 England. It is harmful to rasplierries, forming galls on the canes as 

 on the bramble. The size of the galls is very variable, inasmuch as 

 the gall may be simply a slight excrescence. 



With regard to the description of the species, Theobald says : " In 

 their habits they resemble the CeciiJomi/irhe, infesting plants much in 



