108 BRITISH OAK GALLS. 



their surroundings and are of tlie same texture and 

 colour. 



In the year 1897 M. AV. Beverinck (" Ueber di 

 Sexuelle Generation von (Ji/nips KoUari," ' Marcellia,' 

 YoL i, p. 13) imprisoned a few imagines of C. Kollari 

 on a young tree of Q. cerris, and observed that 

 thev pierced the 1)uds. Upon opening the buds, 

 he found that a number of ova had been deposited. 

 In Octol^er, 1901, the experiment was repeated, 

 and in the following February there were signs 

 of gall growth. By April galls of Arulricus circulans 

 had fully matured, and early in the following month 

 imagines came out, which proved to be those of A. 

 circuhiits. Further experiments were made with a 

 like result — an enormous number of circulans galls on 

 every twig of the experimental tree. 



He also found that out in the open, the galls of 

 G. Kollari showed first indications of growth at the 

 beginning of June, or about fonrteen days later than 

 the emergence of A. circulans. This he regarded 

 as a further confirmation of the alliance, and alter- 

 nating, of the two species. He w^as not able to get 

 A. circulans to oviposit in Q. pedunculata. He also 

 believes that A. hurgundus is the sexual form of 

 C. tinctoria. 



Dryophanta agama, Mayr. 

 (Plate XL.) 



Ci/nips agama, Hartig ; Drijopharda agama, Hartig, Miiller, 

 Camerou, Fitch. 



English name of gall. — " The Yellow Pea Grail.'" 



Position of gall. — On the under- surface of the mid-rib and its 

 offshoots. 



Manner of growth. — Single, glabrous, glossy, nodulose (incon- 

 spicuous), oblate. 



Colours. — Pale yellow, orange yellow, yellowish-brown. 



Average dimensions of a mature specimen. — Height, 4 mm.: 

 length, 5 mm. : breadth, 4 mm. 



May be sought during the months of Jvme to August. 



Growth is complete by the end of August. 



