68 



THE ENTOMOLOGIST. 



Neuroteeus numisjiatus. 



appears in July on Que reus sessiUJlora, peclunculata, and 

 pubescens. It is produced on the under side of the leaf as a 

 small, flat disk, adhering to the leaf in one point only ; the 



outside margin soon thickens, until 

 the mature spherical gall obtains a 

 \ diameter of three millimetres. The 

 gall is flat next the leaf; the upper 

 part, however, is convex, and con- 

 siderably indented in the centre ; 

 its brown surface is covered with 

 light brown, smooth, silky hairs, 

 which are turned outwards : the 

 interior of the gall contains a 

 small larva-cell. The galls fall 

 in October and November, pass the winter on the ground 

 where they still continue to swell, and the fly appears in 

 February and March. In the neighbourhood of Vienna the 

 galls are rare, but frequently to be met with in the Leithage- 

 birge mountains. I have received it from Herr Kichner from 

 the district of Budvveis, and from Herr Forel from the 

 borders of the lake of Geneva. — G. L. Mayr. 



We now come to a genus of Ci/nipidce, the productions of 

 which are well marked as a class, lor who has not noticed the 

 oak-leaves in autumn, crowded, so to speak, with little round 

 fungus-looking objects on their under side. It is these which 

 are the galls occasioned by the Neuroteri ; and for some 

 time their nature was a very fertile subject of dispute amongst 

 naturalists; the botanists holding, I believe, to their fungoid 

 or lichenous nature; while the zoologists had a belief in 

 their indebtedness to insect agency. Their vegetal nature 

 was evident; not so the insect, which is almost or quite 

 imperceptible, until the galls fall from the leaf in the autumn, 

 for it is during the winter and spring that the galls, of 

 lenticularis and /u7}iipe/nns more particularly, swell, and the 

 larvae feed up and change into the pupa state ; the gall- 

 makers are evolved about March. It was Reaumur who first 

 discovered the little larva under the galls, and thus set at 

 rest the question of their production. Westwood ('Arboretum 

 Britannicum,' p. 1827) and Smith (Trans. Ent. Soc, London, 

 vol. ii., Proceedings, p. xlii.) were the first to notice it in this 

 country. The genus Neuroterus, like Cf/nips and some few 



