OAK GALL-FLIES. Ill 



The foUowiug species of Cynipidae are not arranged systematically 

 or by their modern genera, but so far as practicable by the species of 

 oak on which they live. 



The oak-fig gall-fly. 



Cijnips quercus-ficus Fitch. 



Order Hymenoptera; family Cynipid^. 



Surrounding the twigs of white oaks in a dense cluster, resembling preserved figs 

 packed in boxes, each molded to the shape of those pressing agaiust its sides, hollow 

 bladder-like galls of the pale dull yellow color of a faded oak leaf, each gall produc- 

 ing a small black fly with the lower half of its head, its antennae, and legs pale dull 

 yellow, its hind shanks dusky, and its abdomen beueath reddish-brown, its antenaae 

 with fifteen and in the female thirteen joints. Length .06, females .10, and to the 

 end of their wings .14. (Fitch.) 



Galls which apparently belong to the above species were received 

 June 10, 1882, from Miss Kath. Parsons, South Lancashire, Mass., who 

 found them on the oak at Breakheart Hill, Saugus, Mass., and several 

 of the gall-flies were bred from them between July 1 and July 13. 



Apparently the same kind of galls were found July 20, 1883, in Vir- 

 ginia on Q. alba. From these issued, from August 16, 1883, to April 

 21, 1884, numerous parasites, belonging to the genera Torymus, Ormy- 

 rus, Decatoma, and a Cecidomyid. 



The Cynips, which are wingless, differ from those from Miss Parsons 

 in that they were winged. They commenced to issue January 30, 18S4, 

 and kept on issuing through the whole of February. 



From a few galls, received March 19, 1883, two specimens, also wing- 

 less, issued February 9, 1881, and large numbers of wingless insects 

 issued from a lot of galls collected by Mr. Koebele at Meredith Village, 

 N. H., in September, 1883, in the same month. Among these last was 

 also one winged specimen of probably a different species. (Riley's un- 

 published notes.) 



The oak-potato gall-fly. 



Cynips quercus-batatiis Fitch. 

 Order Hymenoptera; family Cynipid.e. 



A large, hard, uneven swelling, three-fourths of an inch thick and twice or thrice 

 as long, resembling a potato in its shape, growing on white-oak twigs more distant 

 from their ends than the oak-tumor; producing a small black gall-fly with the basal 

 joints of its antennse and its legs dull pale yellow, its thighs and hind shanks black, 

 and its middle shanks often dusky, the antennae in the female with thirteen joints, 

 and the length of this sex .09. (Fitch.) 



The oak-bullet gall-fly. 



Callaspidia quercus-globulus Fitch and Cijnips oneratus Harris. 



Order Hymenoptera; family Cynipid.e. 



Smooth, globular galls the size of a bullet, growing singly, or two, three, or more in 

 a cluster, upon white-oak twigs, internally of a corky texture, each containing in its 

 center a single worm, lying in an oval whitish shell resembling a little egg .15 in 



