BRITISH GALLS 
166 
catkin to resemble a bunch of red currants. Imago emerges 
in May or June. This gall also appears on the leaf; it is 
then greenish-yellow, rarely tinged red. On the upper 
surface of the leaf there is a slight rounded swelling with 
a central scar ; the bulk of the gall is below. It becomes 
dry and rapidly shrivels at maturity. Imago, June, I. 
(Plate V. i.) 244 
Neuroterus baccarum Linn. 245 
Syn. Spathegaster baccarum Linn. 
Connold, Oak Galls, pi. 53 ; Plant Galls, figs. 215, 227. 
Houard, Nos. 1196, 1355. Adler and Straton, Alternating 
Generations, pi. 1, fig. 1 a. 
Hymen- On the lower surface of the leaf, a button-like gall, 
optera 4 to 5 mm. in diameter, below almost plane, glabrous and 
whitish, attached to the leaf by a short and slender stalk. 
The upper surface of the gall is conical, yellowish-white, 
and closely covered with purplish or brown hairs, often 
densely gregarious. Imago, March, II. (Plate V. 4, a.) 
Neuroterus baccarum, form lenticularis 246 
Syn. Neuroterus lenticularis Oliv. 
Connold, Oak Galls, pi. 48 ; Plant Galls, figs. 210, 352. 
Houard, No. 1336. Adler and Straton, Alternating 
Generations, pi. 1, fig. 1. 
, On the under surface of the leaf, a small spherical gall, 
not exceeding 6 mm. in diameter, white or yellowish, 
covered with white or brownish hairs, which fall away at 
maturity; often densely gregarious and deforming the 
leaves. Imago, July, I. (Plate V. 14.) 
Neuroterus tricolor Hartig 247 
Syn. Spathegaster tricolor Hartig. 
Connold, Oak Galls, pi. 54 ; Plant Galls, fig. 216. 
Houard, No. 1356. Adler and Straton, Alternating 
Generations, pi. 1, fig. 4 a. 
,, On the under surface of the leaf, a button-like gall, 
from 2-3 mm. in diameter, not exceeding 1*5 mm. in 
height. Its lower surface is plane or slightly convex, 
with a central short stalk ; the upper surface of the gall is 
yellowish, with a prominent central papilla. The edges 
of the gall are not adpressed to the leaf, and both sides 
of it are sparsely covered with stellate reddish or brown 
hairs. Often densely gregarious. Imago, April or May, 11 . 
(Plate V. 4, b.) 
Neuroterus tricolor, form fumipennis 248 
Syn. Neuroterus fumipennis Hartig. 
Connold, Oak Galls, pi. 46 ; Plant Galls, fig. 207. 
Houard, No. 1338. Adler and Straton, Alternating 
Generations, pi. 1, fig. 4. 
