1898.] 99 



Zomba, February 20th, 1897. In all my experience with Goccidcd I 

 never saw a species so completely infested with parasites as this ; 

 quite 90 per cent o£ the females had been destroyed, and only shell-like 

 fragments of their bodies and the ruptured ovisacs were left. A 

 careful search among the debris at the bottom of the box revealed a 

 couple of minute Hymenopterous insects and a small brown beetle. 

 Whether the work of destruction can be assigned entirely to these 

 insects is doubtful. Judging from the ruptured ovisacs I am inclined 

 to think a larger insect had taken part in the work ; but this could 

 easily be verified in the field by a careful observer. We sincerely 

 trust that Mr. Whyte will give this matter his attention, and be able 

 to clear up this important part in the economy of the pest. 



Chester : November 2^th, 1897. 



OAK G-ALLS. 



BY a. C. BIGNELL, F.E.S. 



Are small oak-trees comparatively free from gall-flies the year 

 following an attack ; or in other words, v^ill a small oak-tree be 

 attacked year after year by gall-flies ? 



I should like to know the opinion of readers of this Magazine 

 on the above subject. 



From my own observations I believe spring-gall-flies will not 

 deposit their eggs on a small tree that had borne bud or bark galls 

 the previous year. 



In 1896 two young oaks, grown in pots over 20 years, were 

 punished by my placing on them several flies of Andricus corticis, 

 with the result that nearly all the young shoots were occupied by 

 Andricus gemmatus ; during the autumn after the departure of the 

 flies the trees appeared to have recovered, and produced a fine lot of 

 buds for the next year's growth ; accordingly, in the spring of 1897, 

 I placed on the same trees several Andricus Sieholdii ; observing these 

 did not take kindly to the surroundings, I placed a second lot on 

 them, but to my surprise not a single one attempted to deposit an 

 egg, neither would they remain on the trees, the only thing that both 

 lots did was to try to escape from their confinement, apparently trying 

 to avoid something very obnoxious. 



Last autumn I obtained from a nursery some stunted young 

 oaks, and placed them in pots with a view of carrying out some gall 

 bi'ceding; these, however, had borne a few Gj/nips Kollari g-A\\i>., -.xwiX 



