90 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.63. 



convex modially and curving downward posteriorly, recalling the 

 form found in diylosidis Ashmead, with a few faint aoiciilae on 

 anterior half; notauli indicated on basal fourth, the median lobe 

 broadl}^ rounded behind; scutellum as in laficeps but pubescent and 

 more narrowly margined laterally ; abdomen a little shorter than the 

 head and thorax united, ovate, rounded on the sides toward the apex, 

 subacute apically, as wide as the thorax, two-thirds as wide as long: 

 first tergite sculptured as in laticeps, without pubescence; second as 

 wide as long, without pubescence, twice as wide apically as basally, 

 the sides curved, sculptured as in laticeys except that the lateral 

 striae do not extend beyond the middle of the segment; terminal 

 segments unsculptured, united half as long as the second, each with 

 a row of white hairs across its middle; wings hyaline, extending the 

 length of the last two segments past the apex of the abdomen. 

 Black; antennal club, coxae, and last joint of each tarsus piceous; 

 scape and legs (except tarsi and anterior tibiae apically which are 

 touched with yellow) reddish-brown. 



Male. — Length 1.3 mm. Antennae moderately slender; pedicel 

 one-third longer than wide ; third joint nearly as wide as the pedicel, 

 transverse, half as long as the fourth which is as long and a little 

 wider than the pedicel, not much narrowed basally, its lower side 

 straight; joints five to nine subequal in length and width, distinctly, 

 but only slightly, longer than wide; joint ten as long as three and 

 four united, acute at apex; abdomen egg-shaped, a little longer than 

 the thorax, convex above and below, t^vice as long as wide, rounded 

 posteriorly; wings hyaline, extending a little beyond the apex of the 

 abdomen. 



Type locality. — District of Columbia. 



TyjJe.—C&t. No. 2287, U.S.N.M. Type female and allotype male 

 selected. 



Redescribed from the type series, three females and one male. 

 The male is here described for the first time. The types were reared 

 July 31, 1886, from a Cecidomyid gall in the flower bud of Alder. 



63. PLATYGASTER BACCHARICOLA (Ashmead). 



Polygnotus haccharicola Ashmead, Can. Ent., vol. 19, 1887, p. 132. — Cresson', 



Syn. of Hym., 1887, p. 250.— Ashmead, Bull. 45. U. S. Nat. Mua., 1893, 



p! 306 (pi. 13, fig. 2, female).— Brtjes, Bull. 22, Conn. Geol. Nat. Hist. 

 Surv., 1916 (1917), p. 539. 



Female. — Length 1 to 1.2 mm. Head a little over twice as wide 

 as long: occiput striate; cheeks shagreened ; vertex, interooellar area, 

 and space around lateral ocelli, shagreened; frons above highly pol- 

 shed, below finely aciculate; antennae moderately stout, gradually 

 thickened toward tip; joints three and four united distinctly shorter 

 and a little narrower than the second; four slightly longer and wider 



