112 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION 
length; producing sometimes ■ black gall-fly with tawny-red legs and the second 
reinlef of its wings elbowed or angularly ben I backwards, it> length .15; sometimes 
■ smaller tly | C. oneratu*) of a clear pale yellow color, almost white, with a broad 
black stripe the whole length of its back, which color in the males is more extended, 
reaching down upon the sides, its length .12. (Fitch.) 
These species arc parasitized by two chalcid flies, Maeroglenes querci- 
globtUi Pitch and Pteromalu* onerati Fitch. 
TlIK WOOL-SOWEB GALL-PLY. 
Cynipa *t initiator Harris. 
Order Hy.menupteka: family Cyxipid.e. 
A round mass resembling wool, from the size of a walnut to that of a goose egg, 
growing on the side of or surrounding white-oak twigs in June, of a pure white color, 
or tinged or speckled with »*ose-red, and in autumn the color of sponge; producing 
small shining black gall-flies with bright tawny yellow Legs and antenna-, and in the 
female the head and thorax cinuamou-red; their antennae of fifteen aud fourteen 
joints; length .08, aud females .11 inch. (Fitch.) 
The oak-tumok gall-fly. 
Cynips guercus-tuber Fitch. 
Order Hymenoptera; Family Cyxipid.e. 
On or uear the euds of the small limbs and twigs of the white oak, hard irregular 
swellings thrice as thick as the twig below them, the bark upon them of a brighter 
cherry -red color than elsewhere, and their substance internally corky and woody; 
produced by the stiugs of a small black gall-fly, with dull pale yellow antenme, mouth, 
and legs, its hind shanks and its antenme towards their tips being dusky, its length 
.08 and to the tips of its wings .13. (Fitch.) 
The oak-tree gall fly. 
Cynips qnercus-arhos Fitch. 
Order Hymenoptera: family Cyxipid.e. 
Swellings similar to those above described, growing on the tips of the limbs of aged 
and large white-oak trees ; producing a small black gall-fly having all its legs and 
antennae of a bright pale yellow color, and one more joint in the latter organs than 
in the preceding species iu the males, which sex is .06 in length, aud to the tips of 
its wings .JO. (Fitch.) 
The followiug observations are from Professor Riley's unpublished 
notes: 
('ij)iips quercua-seminator Harris. 
Galls of this species were found on twigs of Q. alba in May and June in Virginia, 
aud the flies and several species of Chalcidians issued from them. 
The Cynipids are the true sexes, and were issuing June 13, and the parasites, among 
which was also a Cecidomyid, issuing from June till November 12. 
Many of the galls were placed with a small tree of Q. alba and covered withgauze, 
for observation, but notwithstanding the great number of flies, not a single gall was 
produced on leaves or twigs. 
