CHAP. CV. CORYLA‘CEA. QUE’RCUS. 1929 
species was introduced into England in 1822; but we have never seen it, and we are not aware that 
there is a living plant of it in the neighbourhood of London. 
i 
Y 
0) \ 
The gall fly of Q. infectoria 
belongs to the family Cyni- 
pide Westw. (Diplolepariz 
Latreille.) Amongst the 
excrescences, or galls, pro- 
duced by the punctures of 
the different species of this 
family of insects, the galls, or 
nut galls, of commerce (in 
French, galles and noix de 
galle; in German, gail-apfel; 
in Italian, galle and galluzze ; 
in Latin, galla; in Arabian, 
afis; in Hindostanee, mayu- 
phal; and in Persian, mayer) 
are by far the most valuable, being much employed in the manufacture of ink, 
as well as occasionally for medicinal purposes. These galls, which, when full 
grown (fig. 1821.), are of the size of a boy’s marble, of “ 
a rounded form, and rather uneven surface, are at- 
tached to the slender stems of the branches of Q. in- 
fectoria, and are produced by the Dipldlepis, or, more 
properly, Cynips Galle tinctoria Oliv. Enc. Méth., 
vi. p. 281.; Cynips scriptorum Kirby and Spence Intr., 
i, p. 319. This insect (fig. 1822. d) is of a pale 
brown colour, and may often be found enclosed in the 
galls sold in the shops of the druggists, &c.; these 
galls having been collected before the insect had made 
Itsescape. Jig. 1822. @ is a section of one of these 3 
galls. The natural history of this family of insects ° 
may be stated in a very few words, although the phy- 
siological nature of the changes which take place in 1822 $ 
the action of the juices of the plants attacked by them, whereby galls of a 
very great diversity of form are produced, has not been ascertained. The 
female Cynipide are furnished with an instrument, or ovipositor, of a curved 
form, and, for the most part, concealed within the abdomen, the extremity only 
