REPORT OF THE STATE ENTOMOLOGIST I905 



125 



being sublateral, each consisting of a circular, chitinous elevation 

 with a median depression or aperture. 



Black locust midge (Dasyneura pseudacaciae Fitch) . 

 Occasionally young leaves of black locust are badly deformed by 

 being folded together so as to produce peculiar podlike galls about 

 inch long. This is the work of the above named small, black 

 midge or fly, which probably deposits two or three eggs in each 

 unfolding leaf. The young maggots hatching therefrom produce 

 sufficient irritation to prevent the leaf unfolding, and its free edges 

 adhering together more or less form a fairly perfect gall, within 

 which tlie nearly helpless larva develops to maturity. Sometimes 

 this species is very numerous, since we received specimens from 

 Mr C. L. Williams of Glens Falls, N. Y., accompanied by the 

 statement that some parts of a black locust hedge had nearly every 

 leaf infested by this little insect. It is rarely so abundant as this, 

 though Dr Smith records it as a common species in New Jersey. 



This insect is with very little doubt the same as that described 

 under the above specific name and referred to the genus Cecidomyia 

 by Dr Fitch in his 5th report for the year 1859, page 53. Some 

 years later Baron Osten Sacken described what is very probably the 

 same form, under the name of Cecidomyia gleditchiae. 

 There are some inconsistencies in colorational characters between 

 the two descriptions, but these perhaps may be partly explained 

 by one describing more matured or even driec 

 the other characterized fresh individuals. 



Description. This little fly was described by 

 Dr Fitch as follows: "A small, blackish midge, 

 the base of its thorax tawny yellow, its abdomen 

 pale yellowish, with the tip dusky and clothed 

 with fine hairs, as is also the neck; its legs black, 

 with the thighs pale except at their tips ; its wings 

 dusky, feebly hyaline, with the fringe short ; its 

 antennae with 13 short cylindrical joints sepa- 

 rated by short pedicels; its length, .065 inch to 

 the tip of the body." 



The above description varies somewhat from 

 dried specimens bred by us in July, and the dis- 

 crepancy is probably due to the drying of the 

 specimens. 



Female. Antenna dark brown, moniliform, extending to the base 

 of the wing and composed of 14 stout, closely set segments, each 

 rather sparsely clothed with long, somewhat stout, curved setae 

 arising from conspicuous elevations. Careful focusing brings out 

 more or less distinctly on each segment a middle and subapical, 



specimens while 



Fig. 34 Dasyneura 

 pseudacaciae. an- 

 tcnnal segments of 

 female, much enlarged 

 (Original) 



