368 NEW YORK STATE MUSEUM 



dd Palpi uniarticulate 



e Abdomen yellowish ; mesonotum reddish brown ; 

 female, bred from apical rosette gall on Euthamia 

 lanceolata n. sp., C. 784 

 ee Abdomen reddish or light yellowish brown; meso- 

 notum reddish brown; female, bred from a hollow 



gall on Bigelovia bigeloviae Ckll., C. 1070 



hbbb Antennae with 13 to 14 segments 



c Abdomen brownish red; mesonotum reddish brown; female, 



bred from suboval flower or bud galls on Gutierrezia 



(Asphondylia) gutierreziae Ckll., C. 31742 

 cc Abdomen and mesonotum dark brown ; female, bred from gall 



on Audibertia audibertiae Felt, C. 1029 



bbbhb Antennae with 12 segments 



c Antennal stem with a lengtli Y^ that of the basal enlargement 

 d Abdomen and mesonotum dark brown ; palpi uniarticu- 

 late; male, bred from gall on Audibertia 



audibertiae Felt, C. 1029 

 cc Antennal segments sessile or nearly so 



d Abdomen pale yellowish ; palpi biarticulate 



(Oligotrophus) Sackenomyia acerifolia Felt, C. 38 



OLiGOTROPHUs Latr. 

 This group, as at present restricted, comprises a number of forms 

 related to Dasyneura and Rhabdophaga and differing therefrom by 

 having the claws simple. It is separated from more closely allied 

 genera by the triarticulate palpi. The wing is illustrated on plate 

 36, figure I, 



Key to species 

 a 13 or 14 antennal segments; abdomen dark brown 



b 13 or 14 sessile antennal segments, the 5th with the basal enlargement 

 J4 greater than its diameter, the 3d palpal segment twice the length 



of the 2d ; female, bred from Betula seeds 



b e t u 1 a e Winn., C. 964 



bb 14 subsessile antennal segments, the Sth with a stem about J4 the 



length of the basal enlargement, which latter has a length twice its 



diameter; the 3d palpal segment is 3 times the length of the 2d; 



female v e r n a 1 i s n. sp., C. 60 



aa IS antennal segments 



b Abdomen dark brown, the 5th antennal segment with a stem J/^ the 



length of the basal enlargement; male, bred from Betula seeds 



b e t u 1 a e Winn., C. 964 

 aaa 16 antennal segments 



b Abdomen fuscous yellowish, the 5th antennal segment with a stem ^ 

 longer than the basal enlargement; bred from an apical rosette 

 gall on Solidago i n q u i 1 i n us n. sp., C. ai655a 



