DESCRIPTIONS OF OAK-GALLS. 



205 



linear apical leaves lengthen, and mostly grow uniformly 

 from the whole exterior of the nearly globular gall. It 

 seldom remains quite green ; the apical leaves generally 

 redden, or the whole gall becomes reddish in colour. The 

 style, with its accompanying depression, is always recog- 

 nisable, even when it does not appear set on opposite the 

 footstalk. In section it shows that the involucre, as well as 

 the lower part of the germen, is enclosed in a green, soft 

 mercnchyma, which contains several larva chambers. The 

 fly appears at the end of May or beginning of June, although 

 1 once obtained them as early as May 19th. — G. L. Mayr. 



Fig. 91. — Gall of Spatlier/aster glandiformis, and in section. 



This inconspicuous and early Turkey oak gall is not 

 likely to occur in Britain. Syiieigus 2 haumacera, Daliii., 

 Ceropires Cerri, Mayr, and Megasligmus dorsalis, Fabr., 

 were bred sparingly with the gall-maker in May or June of 

 the first year. — E. A. Fitch. 



Fi''. 9:2. — Sections of acorn, with galls of Andriciis (/landiuni. 



92. Andricus ylandium, Giraud. — If we cut tiirough the 

 fallen acorns of the Turkey oak in autumn we often find in 

 their interior a remarkable thickening of the brown shell, 



