206 NEW YORK STATE MUSEUM 



Phytophaga fraxini n. sp. 



This yellowish midge was reared June 2 2d from the leaf petioles 

 of ash, Fraxinus, taken at Poughkeepsie, N. Y., June g, 1908. 

 Infested shoots were collected at Albany, N. Y., June 13, 1913. 



Gall. Numerous pale yellowish larvae were observed at the 

 base of the terminal leaf petioles. They prevent the normal develop- 

 ment of the central, leading bud. There was no noticeable de- 

 formity. 



Larva. Length 1.5 mm, pale yellowish. Head long, slender; 

 antennae rather short, tapering; breastbone bidentate. teeth broadly 

 rounded, the shaft rather slender. Skin finely shagreened; posterior 

 extremity broadly rounded. 



Male. Length 2 mm. Antennae nearly as long as the body, 

 sparsely haired, fuscous yellowish, the basal segments yellowish; 

 14 segments, the fifth with a stem about one-fourth the length 

 of the basal enlargement, which latter has a length about three 

 and one-third times its diameter; terminal segment rather stout, 

 with a length about three times its diameter and bearing apically 

 a rather long, stout, fingerlike process. Palpi; the first segment 

 short, stout, subquadrate, the second with a length about three 

 times its diameter, the third a little longer and more dilated and 

 the fourth as long as the third. Face yellowish. Mesonotum 

 light brown, the submedian lines yellowish, sparsely haired. 

 Scutellum yellowish orange, postscutellum, abdomen and genitalia 

 yellowish. Wings hyaline, costa light brown, the third vein well 

 beyond the apex; halteres yellowish transparent. Coxae and femora 

 basally yellowish, the distal portion of femora and tibiae light fuscous 

 yellowish, tarsi mostly dark brown; claws long, slender, strongly 

 curved, the pulvilli as long as the claws. Genitalia; basal clasp 

 segment long, stout; terminal clasp segment short, stout; dorsal 

 plate short, stout, deeply and triangularly emarginate; ventral 

 plate long, deeply and triangularly incised. 



Female. Length 2.5 mm. Antennae extending to the fourth 

 abdominal segment, sparsel}^ haired, fuscous yellowish, basally 

 yellowish; 14 segments, the fifth with a stem one-fourth the length 

 of the basal enlargement, which latter has a length three times 

 its diameter; terminal segment produced, with a length five times 

 its diameter, apically a pyriform appendage. Palpi; the first 

 segment short, stout, subquadrate, the second rather stout, with 

 a length nearly three times its diameter, the third one-half longer 

 than the second, more slender and the fourth one-half longer than 

 the third, more dilated. Color practically as in the male, except 

 that the mesonotum is slightly darker and the setae on the abdomen 

 more evident. The wings are slightly more hairy. Legs and claws 

 practically as in the opposite sex. Ovipositor about as long as the 

 body, slender, the terminal lobes long, tapering, narrowly rounded. 

 Type Cecid. aiS4i. 



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