ON THE COMMON OAK 
173 
Lepidop 
tera 
Diptera 
5 > 
Acari 
Near the extremity of a branch, a more or less incurved 
swelling, two or three times the normal diameter of the 
branch. Caterpillar in the pith. Exit below. 
Stenolechia gemmella Linn. 276 
Houard, No. 1300. 
On the leaf. The midrib swollen, 5 to 8 mm. long, colour 
yellowish, also on petiole, the affected part attaining three 
times the normal diameter. Caterpillar white sprinkled 
with brown hairs, head black. M. E., rarely M. G. 
Heliozela stanneella Fisch. v. R. 277 
Houard, No. 1316. 
Terminal internodes not expanding, the leaves forming 
loose tufts, crinkled along their swollen veins. Larvae 
whitish, gregarious, leaping. 
CONTARINIA QUERCINA Rub. 278 
Trail, Scottish Nat., iv., 1877. Houard, No. 1207. 
One or more of the marginal lobes of the leaf thickened, 
folded downwards and flattened upon the lower surface, 
forming a pouch which is reddish above and spotted with 
red and yellow below. Larvae gregarious, two to six, 
whitish. (Plate VIII. 9, 10.) 
Macrouiplosjs dryobia F. Low 279 
Syn. Diplosis dryobia F. Low. 
Houard, No. 1306. 
The edges of the leaf segments folded over on the 
upper surface ; within each fold are one to four pale 
orange-yellow larvae. There is no marked discoloration 
of the affected parts. 
Macrodiplosis volvens Kiefifer 280 
Syn. Cecidomyia roboris Hardy. 
Connold, Oak Galls, pi. 63 ; Plant Galls, fig. 200, and 
in both wrongly attributed to M. dryobia. Trail, in Wild 
Fauna and Flora of Kew Gardens, 1906, p. 44. Houard, 
No. 1307. 
On the lower surface of the leaf, adjacent to the larger 
vein, a felt of abnormal hairs of two kinds : one hyaline, 
very long and much contorted ; the other shorter and 
cylindrical, scarcely bent, and often swollen into a club 
at the top. Erincum quercinum Persoon. 
Eriophyes quercinum Can. 281 
Trail, in Wild Fauna and Flora of Kew Gardens, 1906, 
p. 44. Houard, No. 1313. 
