NORTH AMERICAN TETRASTICHES BURKS 527 



margins of compound eyes; apex of scape reaching level of ventral 

 margin of anterior ocellus ; pedicel three-quarters as long as first funi- 

 cle segment, all funicle segments subequal in length, first slightly 

 shorter than second; club as long as two distal funicle segments; 

 length of malar space one-half as great as height of compound eye; 

 postocellar line one and one-half times as long as ocellocular line. 

 Mesopraescutum wider than long and bearing three or four long 

 bristles at each lateral margin ; submarginal vein of forewing with one 

 dorsal bristle: apex of hindwing blunt, fringe at posterior margin 

 one-third as wide as wing at hamuli. Surface of propodeum strongly 

 reticulated, paraspiracular carinae present ; mesal length of propo- 

 deum one-half as great as length of mesoscutellum ; propodeal spira- 

 cles almost touching anterior margin; gaster rounded, short, equal 

 in length to thorax; apices of ovipositor sheaths just reaching apex 

 of abdomen, occasionally not quite reaching apex. 



Male. — Length, 0.6-0.9 mm. Pedicel and first funicle segment of 

 antenna equal in length, three distal segments of funicle equal in 

 length and each one-eighth longer than first, funicle segments slightly 

 enlarged near bases, bearing long setae, as in figure 16, I; gaster as 

 long as thorax. 



Type locality. — Urbana, 111. 



Types. — U. S. N. M. No. 385; paratypes in Illinois State Natural 

 History Survey Collection. 



Host. — Reared from the nest of a spider wasp, Phanagenia bom- 

 bycina (Cresson), but may not be a primary parasite of it. 



Distribution . — Illinois. 



TETRASTICHUS LISSUS, new species 



Thorax black, with iridescent blue luster; head and gaster very 

 dark brown or black, with very faint iridescence; antennal scape, bases 

 and apices of femora, tibiae, and basal three segments of tarsi light 

 yellow or white ; flagellum of antenna and apical segment of tarsi tan. 



Female. — Length, 1.6-1.7 mm. Antennae inserted slightly ventrad 

 of level of ventral margins of compound eyes ; apex of scape not reach- 

 ing level of anterior ocellus; pedicel one and one-half times as long 

 as first funicle segment, all three funicle segments of equal length 

 and each almost as wide as long, club as long as funicle; height of 

 compound eye only one and one-quarter times as great as length of 

 malar space; postocellar line one and one-half times as long as ocelloc- 

 ular. Mesopraescutum with two or three rather irregular rows of 

 bristles at each lateral margin ; longitudinal grooves of mesoscutellum 

 obliterated at anterior margin; submarginal vein of forewing with 

 four or five dorsal bristles, marginal vein short, less than twice as 

 long as stigmal vein; apex of hindwing blunt, fringe at posterior 



