86 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 63. 



tinct, striate, the striae not quite attaining the middle of the segment; 

 area between the foveae shortly fluted; segments three to six united 

 three-fifths as long as the second, unsculptured; wings hyaline, reach- 

 ing to the apex of the abdomen. Black; antennae and legspiceous; 

 trochanters brownish; anterior tibiae apically, all tibiae basally, and 

 all tarsi (except the last joint of each) yellow. 



Male. — Length 1.10 mm. Pedicel twice as long as wide; joint three 

 wider than long, half as long and as wide as two; four as long as the 

 pedicel, very little longer than wide, widened just below the apex, 

 subacute below; joints five to nine as long as the pedicel; six to nine 

 one and one-third times as long as wide : ten as long as two and three 

 united, acute apically; abdomen obovate, rounded behind, narrower 

 than the thorax, slightly over twice as long as wide, strongly convex 

 above, nearly as long as the head and thorax united; tergites three 

 to seven short, united half as long as the second, each traversed 

 by a row of punctures; wings hyaline, extending two-thirds the length 

 of the second tergite past the apex of the abdomen. Coloration as 

 in the female. 



Type locality. — Glen Echo, Maryland. 



Type.—Csit. No. 25440, U.S.N.M. Six paratypes in Collection 

 Fonts. 



Described from two females and nine males which I collected at 

 Glen Echo, July 19, 1919, on the leaves of Liriodendron tulipifera 

 Linnaeus. The species is probably parasitic on some gall making 

 Dipteron infesting the tulip tree. 



The female paratype has the abdomen and part of the antennae 

 lost. All the types are mounted on card points. 



50. PLATYGASTER EUROTIAE (Ashmead). 



Polygnotus eurotiae Ashmead, Bull. 45, U. S. Nat. Mus., 1893, p. 315. 

 Female. — Length 1.3 mm. Habitus of Memalis; head a little over 

 twice as wide as long, slightly emarginate posteriorly; occiput and 

 oheeks behind transversely aciculate; vertex rounded, striate medially 

 finely shagreened laterally; frons with fine wavy aciculae; antennal 

 structure as in Memalis, all the joints longer than wide; thorax seven- 

 ninths times as wide as long, slightly narrower than the head; pro- 

 notum aciculate on the sides, smooth posteriorly; median area 

 transverse, unsculptured; mesonotum convex, highly polished, with a 

 few faint wavy aciculae anteriorly; notauli distinct on basal two- 

 thirds of mesonotum; median lobe rounded posteriorly as in hiemalis; 

 first tergite ^vith a few hairs on its edges ; second hairless ; abdomen 

 shaped generally as in hiemalis, a little more pointed apically, slightly 

 longer than the thorax; first tergite twice as wide as long, elevated 

 anteriorly; dorsolateral ridges well defined, the median area quad- 

 rate, smooth, with a median carina; second tergite a little longer 



