54, [March, 



natural selection, which has probably influenced the under-side colora- 

 tion — yet in this particular instance the cause of the difference in the 

 specimens is by no means apparent, as they were reared under 

 absolutely identical conditions, and I certainly hesitate to attribute it 

 to the fact that one of them was a day longer in the larval stage. 



Estcourt, Natal : 



January, 1897. 



SOME FURTHER OBSERVATIONS ON BRITISH OAK GALLS. 

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



Andricus (ApniLOTiiRix) corticis. — According to Cameron's 

 Monograph, vol. iv (Ray Soc), on the Oak Galls, the time of the 

 appearance of this fly is July ; from my observations it is March and 

 April. AVhen collecting galls in Cann Wood, in December, 1892, I 

 found a cluster of galls of A. corticis embedded in new bark growing 

 over an old wound caused by a cart wheel two or three years previously ; 

 in removing the galls I accidentally opened one during the Work of 

 removal, and I then observed that the fly was perfectly mature and ready 

 to emerge, its companions, however, did not make their way out until 

 March 4th following. 



Andricus (Aphiloturix) globuli. — Cameron and Adler state 

 that this fly appears in April ; my experience is January. I was very 

 fortunate in obtaining galls from Dr. Chapman of Hereford on October 

 ]3th, 1894, at this time they were quite ripe and falling to the ground. 

 In January, 1896, from 2nd to the 14th, I bred 25 flies out of 238 

 galls received ; relying on the above authorities, I did not keep a 

 sharp look out for them, consequently I have no doubt many escaped 

 in December. 



Andricus ramuli. — With reference to my note, Ent. Mo. Mag., 

 September, 1895, I mentioned having only bred males ; from a gall 

 obtained at Loddiswell last June I bred males and females, the great 

 majority, however, were the latter. 



Andricus (Aphilothrix) fecundatbix. — A few notes I have 

 of this species may be of some assistance to a future writer on oak 

 galls. In August, 1887, I collected a number of these galls, and as 

 the flies did not appear in April, 1889, I made a search in June and 

 opened several ; those operated upon contained fat, full grown larvse. 

 1 placed one in a glass tube, on September 10th it had changed to pupa, 

 and on the 23rd to a fly. In May, 1890, 1 opened the remainder, about 



