558 PROCEEDINGS OF THE NiAfTTOlNAlL. MUSEUM vol. 93 



gular part of scapulae, mesal lobe of metanotum, apices of coxae, 

 trochanters, bases and apices of femora, tibiae, and basal segments of 

 middle and hind tarsi white or light yellow. 



Female. — Length, 2.5-3.0 mm. Antennae inserted considerably 

 dorsad of level of ventral margins of compound eyes, as in figure 16, 

 a; apex of scape slightly exceeding level of vertex, funicle segments 

 slender, elongate, first segment one and one-fifth times as long as 

 second, club one and one-fifth times as long as second segment; length 

 of malar space five-eighths height of compound eye; postocellar and 

 ocellocular lines equal in length. Mesopraescutum one-third wider 

 than long and bearing one and a partial second row of bristles at each 

 lateral margin ; submarginal vein of forewing with four or five dorsal 

 bristles; stigmal vein one-fourth as long as marginal vein; hindwing 

 blunt at apex, fringe at posterior margin one-fifth width of wing at 

 hamuli. Surface of propodeum faintly reticulated, median carina 

 only present; mesal length of propodeum almost one-half as great 

 as length of mesoscutellum ; propodeal spiracles contiguous with 

 anterior margin ; gaster elongate, one and two-fifths times as long as 

 thorax. 



Male. — Length, 1.7 mm. Scape bearing a small darkened anterior 

 carina near apex; all funicle segments equal in length and each one 

 and two-fifths times as long as pedicel, funicle segments enlarged near 

 bases and bearing conspicuously long bristles, club one-half as long as 

 funicle; gaster as long as thorax. 



Type locality. — Tulsa, Okla. 



Type.— U.S.N.M. No. 20244. 



Host. — Associated with joint worm, Harmolita sp., in grass stems; 

 actual host unknown. 



Distribution . — Oklahoma, Utah. 



TETRASTICHUS ARGYRUS, new species 



Body black, clothed with long, silver-colored bristles ; f rons, anten- 

 nae, most of femora and tibiae, front tarsi and apical segment of mid- 

 dle and hind tarsi, and small areas at base and apex of gaster dark 

 brown ; darkened parts of tibiae lighter brown than those of femora ; 

 bases and apices of femora and tibiae and basal three segments of 

 middle and hind tarsi light yellow or white. 



Female. — Length, 2.0 mm. Entire body elongate, slender. An- 

 tennae inserted at level of ventral margins of compound eyes; apex 

 of scape reaching level of ventral margin of anterior ocellus; funicle 

 segments elongate, club short, first and second funicle segments equal 

 in length and each almost one and one-half times as long as pedicel, 

 third segment slightly shorter than second, club only one and one- 



