164 THE OAK GALLS AND GALL INSECTS 



The gall appears in August or September, falling to the 

 ground in October before the larva is mature. The flies emerge 

 at the end of October, or even as late as November, and prick 

 the buds for oviposition. Sometimes the perfect insect does not 

 emerge until March of the following year. 



Man)' parasitised galls remain on the leaves during the 

 winter, either on the ground or still attached to the tree. 



Though I have been able to breed the fly, I have not 

 succeeded in carrying out any successful experiment with regard 

 to the generation cycle of this species. 



Dr. Adler, who mentions this species as belonging to the 

 genus Neuyoferus, but at the same time proposes to separate it 

 from that genus, gives Neurotevus apvilinus as the probable sexual 

 generation, in which view he is supported by Professor IMayr. 



As mentioned in the case of Neurotevus apvilinus, other forms 

 are given b}^ different authors as representing the sexual gene- 

 ration of this species. 



OCCURRENCE IX EPPIXG FOREST. 



Andricus osireus. Very abundant. Although this gall usually 

 occurs on the back of the leaf, this is not always the case, and it 

 may occasionally be found on the front. As a rule it is situated 

 on the mid rib, but sometimes on the lateral veins. There may be 

 one or more galls on each leaf. I have sometimes found as 

 many as six. 



There is a distinct mark or scar left on the leaf vein after 

 the gall has fallen, due to the two dried membranes, which were 

 originally present at the base of the gall on each side. First 

 appearance noted, August 14th. 



(21). Agamic Form. XI. Andricus solitarius (Fonsc). 

 Iniquilines. Sijnevgus vulgaris (Htg.), S. facialis (Htg.) and 

 5. radiatus (IMayr), 



Gall. 



Spmdle shaped and pointed, widest near the base. Green in, 

 colour when young, reddish brown later. A fresh gall is covered 

 w^ith ferruginous hair ; this is subsequently worn off, the gall 

 becoming quite smooth and brown. The larval cavity is fairly 

 large and the walls comparatively thin. It is found both in the 

 terminal and axillarv buds. 



