DRYOPHANTA DISTICHA. 111 
seldom will as many as fifteen or twenty galls be found 
on one bush ; but when this does occur the contiguous 
bushes may be searched in vain for more specimens. 
This gall is very distinctive in appearance and 
construction. It is firmly attached by a very small 
pointed portion of its base. The point of attachment 
does not show on the upper surface of the leaf. It 
may be found more frequently on oak trees and bushes 
in woods than on those along hedgerows ; occurring 
rather sparingly, not many leaves on the same branch 
being galled, and, seldom more than six or eight 
specimens on one leaf. 
The interior is bilocular ; a condition caused by the 
convergence of the inner walls to form a thin hori- 
Fie. 12.—Three aspects of the same gall caused by Dryophanta disticha. 
a. Side. B. Top. c. End. All nat. size. Dele. ad nat. E.C. 
zontal division devoid of any opening. The upper 
cavity is tenantless. The lower cavity is the larval 
chamber. The imago eats its way out through the 
base of the structure. 
Exteriorly the gall is glabrous, slightly glossy, and 
unique in outline. The upper portion is distinctly 
umbilicated, from the centre of which there arises, in 
some specimens, a minute papilla. When viewed 
under a lens, most of the galls are seen to be studded 
with few, or many, raised brown spots. The shape of 
the gall’ is sometimes circular, but normally it is 
longer than broad, the height being about the same as 
— the breadth. 
This species is not mentioned in ‘ Alternating 
Generations’; and it appears to have escaped the 
notice of most British gall collectors. 
