THE ENTOMOLOGIST. 99 
Andricus nodulti.—This little gall, like 
the preceding, is invisible from the ex- 
terior, being embedded in the bark of 
Quercus pedunculata and Q. pubescens. 
A small spherical or oval swelling is 
observable on the young shoots of the 
Quercus pedunculata, raising the bark 
or rind from 1°5 millemetres to 2 mille- 
metres in diameter, and beneath this 
swelling is situated the gall. On Quercus 
pubescens the swelling occasioned by 
this gall is still less perceptible, on 
account of the tomentum on the surface, 
and sometimes it is entirely absent. It 
is best to look for these galls at the end 
of September, when the perfect insect 
emerges: after some have escaped, and 
have left little circular holes in the rind, 
it is easier to watch the remainder, as a. b. 
they usually follow in the course of a few | axppreus NoDULL 
days. The circular aperture, made by ». A section. 
the perfect insect on its escape, is 
scarcely half a millemetre in diameter. The oval gall, only 
1'3 millemetre in length, is situated either between the bark 
and the wood, or in the wood itself, and is placed longitudi- 
nally with the twig: it is white, and closely surrounded by 
wood and bark; it has a thin covering, and contains one 
larva cell. On the twigs of Quercus pedunculata the 
externally-visible swelling subsides after the escape of the 
perfect insect, and becomes a blackish coloured speck, with 
a circular aperture in its middle. In Quercus pubescens you 
are frequently unable to detect the swelling at all, and if any 
unevenness has existed it remains after the perfect insect has 
made its escape, and the surface of the bark does not change 
colour. This gall is occasionally on leaf-pods and on petioles. 
It is probable that the gall named C. Turionum, with which 
I am unacquainted, belongs to this species.—G. L. Mayr. 
Mayr mentions three inquilines inhabiting the galls of 
Andricus noduli: Ceroptres arator, Hart., Sapholytus con- 
natus, Hart., and Synergus apicalis, Hart. The first appears 
in May and June of the second year; the third in May of 
the second year.—Francis Walker. 
