84 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.63. 



This species is rather variable. The characters of color and size 

 are inconstant and the comparative lengths and widths of the last 

 four abdominal segments in the female are not denifite. The segments 

 are telescopic and may be protruded or retracted so that the trans- 

 verse row of hairs may be in the middle of the exposed part of the 

 segment or under the preceding segment. 



48. PLATYGASTER HEIMALIS Fofbes. 



Platygasicr heimalis Forbes, Psyche, vol. 5, 1889, p. 39. 



Polygnotus heimalis (Forbes), Ashmead, Bull. 45, U. S. Nat. Mus., 1893, p. 311. — 

 Brues, Bull. 22, Conn. Geol. Nat. Hist., Surv., 1916 (1917) p. 537. 



Female. — Length 1.4 mm. Head twice as wide as long, not emar- 

 ginate posteriorly, shining; occiput rather finely transversely striate, 

 the vertex nearly smooth, striate medially; interocellar area faintly 

 shagreened; frons finely obliquely aciculate; antennae rather slender, 

 all of the joints longer than wide; pedicel twice as long as wide; 

 fourth joint as long and as wide as the sixth; fifth a little narrower; 

 joints seven to nine one and one-half times as long as wide, cylindrical; 

 ten as long as five and six united, sharply pointed apically ; thorax about 

 two-thirds as wide as long, convex above, highly polished; pronotum 

 aciculate laterally ; median area transverse, unsculptured, the carinae 

 curved outwardly in the middle; mesonotum finely shagreened anteri- 

 orly, mostly polished; notauli short, the median lobe rounded api- 

 cally, broader than in hurJcei; scutellum transverse, convex, unsculp- 

 tured; abdomen a little longer than, but onl}^ as wide as, the thorax; 

 first tergito twice as wide as long, rounded above; median area not 

 distinctly defined, the longitudinal carinae numerous and none more 

 prominent than others: foveae on second tergite with a few striae 

 extending to about the middle of the segment; area between the 

 foveae with a few short carinae; each of the last four tergites with 

 row of hairs across it (sometimes hidden under the segment in front) ;. 

 wings hyaline, ex,tending half the length of the abdomen past its 

 apex.. Black; antennae and legs in most part piceous; apices of 

 anterior tibiae and tarsi (except last joint of each) lighter, brownish. 



Male. — Length 1.4 nmi. Head slightly emarginate posteriorly; 

 mesonotum anteriorly with fine undulating aciculae; third antennal 

 joint button-shaped, distinctly narrower than the pedicel; fourth 

 joint more than twice as wide apically as basally, wider apically than 

 the scape, strongly produced below, almost L shaped, the inner sur- 

 face of the L curved; joints five to nine about one and one-half times 

 as long as wide; abdomen egg-shaped, narrowed anteriorly, about as 

 long as and a little wider than the thorax, seven-tenths times as 

 AA'-ide as long; first two segments shajn-d and sculptured as in the 

 female; Avings hyaline, extending half the length of the abdomen 

 past its apex. Coloration as in female. 



