74 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. G3. 



the median lobe blunt, not projecting over the fovea; sciitellum 

 transverse, highly convex, margined laterally, polished, with a few 

 short scattered hairs on its surface; metapleurae, propodeum, and 

 first tergite at edge, pubescent; abdomen as long as the thorax, con- 

 vex above and below, broadly elliptical posterior to the first tergite, 

 the first segment forming a sort of neck to the rest; second tergite 

 as wide as long, nearly twice as wide apioally as basally, a little nar- 

 rower than the thorax across the tegulae; foveae with a few short 

 striae on their inner slopes; length of second tergite to those follow- 

 ing united as nine is to five; tergites three to five equally long, nar- 

 rowing apically; six wider than long, blunt at apex; wings hyaline, 

 extending a little beyond the apex of the abdomen. Dark reddish, 

 brown; antennae dark brown, the legs lighter. 



Type locality. — Arlington, Virginia. 



Type.— Cat. No. 2292, U.S.N.M. Type selected. 



Redescribed from the type series, five females. There are no male 

 specimens in the type series. Ashmead labeled one specimen as the 

 male and described it but it proves to be a female. 



This species is one of the smallest now included in the genus Platy- 

 gaster. It has somewhat the appearance of dvplosidis Ashmead. 



The types were reared July 3, 1883, from a Cynipid gall, Neuroterus 

 hatalus Fitch. 



40. PLATYGASTER ACTINOMERIDIS (Ashmead). 



Polygnotus actinomeridis Ashmead, Bull. 45, U. S. Nat. Mus., 1893, p. 317. — 

 Brues, Bull. 22, Conn. Geol. Nat. Hist. Surv., 1916 (1917), p. 539. 



Female. — Length 1.3 mm. Head twice as wide as long, not emar- 

 ginate behind, a little wider than the thorax, subconvex in front; 

 occiput finely striate; cheeks subconvex, faintly shagreened above 

 and behind; frons indistinctly aciculate above on the sides, more 

 strongly aciculate below; antennae rather stout, joints seven to nine 

 inclusive being about as wide as long, slightly produced below at 

 their apices; pedicel twice as long as wide, longer and wider than 

 joints three to five; three longer than wide, narrower than four; four 

 slightly longer and wider than five, a little longer thaii^wide; five 

 longer and wider than three; ten twice as long as wide, acutely 

 pointed apioally, its upper side curved; thorax finely shagreened, 

 highly convex above; notauli distinct on basal half of mesonotum ; 

 median lobe narrowly truncated before the soutellum; scutellum 

 slightly transverse, highly convex, polished, sparsely pubescent; abdo- 

 men elliptical, about twice as long as wide, as wide as the thorax, as 

 long as the head and thorax united; first tergite longitudinally fluted, 

 as is also the second tergite between the basal foveae ; median area 

 on first tergite quadrate, flat; second tergite a little longer than wide, 

 the sides nearly straight; basal foveae finely striate, the striae reach- 

 ing slightly past the middle of the segment; tergites three to six 



