STATE AGRICULTURAL SOCIETY. 
819 
OAK. LEAVES. 
fifteen-jointed, in the females thirteen and dusky towards their tips. 
Length 0.08. female 0.11 and to the end of her wings 0.16. 
These galls are not rarij, and in 
the same situation a similar though 
somewhat smaller gall occurs, the 
surface of which is smooth ; but from 
these I have not yet succeeded in 
obtaining the fly. When young the 
surface of these galls is rough, but 
not cracked into the net-work of 
lines that is afterwards seen. The 
interstices between these cracks are 
sometimes flat but oftener show an 
elevated point or pimple in their 
center. The galls are carried to the 
ground with the leaves when they 
fall in autumn, the insects remaining 
in them till the following spring. 
They are of a pale greenish yellow 
color tinged on one side with red, 
when growing, but fade in autumn to the same color as the dead leaves. 
In addition to gall-flies the two following parasites come from these galls, 
hatching therefrom as early as the middle or latter part of April. The 
first of these is oftencst obtained, and what appears to be the same species 
comes also from galls upon whortleberry bushes. 
Tlio Oak-pea parasite, Macroglcnes Querci-pisi, new species. 
Black, the feet white, the hind thighs black and their shanks black in 
the middle, the four anterior thighs black or brown in the middle and their 
shanks white but often in the middle brown, the eyes red. Length 0.10 
to 0.13. 
The Oak-pill parasite, Pteromalus Querci-pilula new species. 
Brilliant green tinged with coppery, the legs light tawny yellow, their 
thighs brilliant green in front, black behind, the middle pair tawny yellow 
with a green-black stripe above and another beneath, the feet dull white 
with black tips, the abdomen with a fine gray beard, its conical tip purple 
black. Length 0.18. 
The gall from which this parasite came had but a single cavity in its 
center, instead of the two usually found there ; and I suspect that having 
consumed one of the larvae of the gall-fly, it breaks through the thin 
partition dividing the cells, and then feeds upon the other, this amount 
of nourishment being apparently necessary to complete its growth to a size 
so much larger than that of the gall-fly and the other parasite which sub¬ 
sists upon it. 
