NORTH AMERICAN HYMENOPTERA. 69 



DR10PHAi\TA Forsler. 



1. D. Clarkei n. sp. 



Galls. — Small, round, smooth, and not quite three-sixteenths of 

 an inch in diameter. They are formed of the buds of the white 

 oak, and are filled with larvas, which are separated from each other 

 by very thin, filmy walls. Most of those in my collection are trans- 

 formed terminal buds, but a few are axillary. I have not learned 

 whether their development takes place wholly in the spring, or 

 Avhether, like several other vernal species, they are partially developed 

 in the preceding year. 



The insects, which appear early in the spring, are of both sexes, 

 and are described as follows: 



Gall-flies.— Females.— i/ertd and entire thorax black and shining; antennae 

 witii tliirteen joints, first short, dark, shining, almost black ; second lighter 

 color, short, almost spherical; third short, but nearly as long as the first two 

 taken together; this and the following three light j-ellowish brown ; remaining 

 joints short and dusky brown. Thorax perfectly smooth, parapsidal grooves 

 heavy, as are also the lines over the base of the wings; polished and shining. 

 Scutellum also smooth, foveaj very small. Legs dark, shining brown, paler at 

 the joints. Wings hyaline, veins moderately heavy, areolet a mere point; cu- 

 bitus pale, decreasing in size as it approaches the first transverse, which it does 

 not quite reach; radial area open. Abdomen black, short, terminal segments 

 mostly concealed in the second. 



Male. — Antenna" with fifteen joints, first black, second globular, third rather 

 short, curved and incised ; legs lighter than those of the female ; abdomen very 

 small ; in size the sexes vary little. Length .08 inch. ; wings, .09 inch. 



This fine species was sent me last spring by Miss Cora A. Clarke, 

 from eastern Massachii-setts. 



2. D. pumiliveutris n. sp. 



I find this remarkable species among my unnamed galls where it 

 has lain for many years. I know nothing of its history further than 

 the description of the galls and insects here given. 



I have received through the mails many boxes of galls that bore 

 no clue to the source from whence they came, or even to the tree or 

 plant on which they grew. Most of them were well-known species, 

 and their source was of comparatively small importance. I think 

 this species must have come in this way. 



These galls, now shrunken and distorted, are pnjbably green, soft 

 and succulent when fresh. They grow in clusters in the axils of the 

 leaves, and when fresh may have been as large as a chestnut or a 

 hazel nut. They seem to have varied considerably in size and form. 



