502 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iis 



Both species are bred from wheat, but E. atripes parasitizes Hessian 

 fly puparia (Phytophaga destructor (Say)) and E. parva destroys 

 larvae of the wheat jointworm (Harmolita tritici (Fitch)). There are 

 also records of both species having been bred from the larvae of the 

 wheat stem sawfly (Cephus cinctus Norton). E. atripes, so far as I 

 have been able to determine, has never been observed emerging from 

 H. tritici larvae. Until suitable life-history studies are made that 

 show that these two species of Eurytoma are either restricted to distinct 

 hosts or will parasitize the same hosts, it seems best to treat them as 

 two good species. 



E. parva displays an additional characteristic that can be used to 

 separate it from E. atripes. The propodeum has a wider median 

 furrow with lateral and median carinae that extend ventrally about 

 three-fourths the length of the propodeum before fading out. Below 

 the furrow the surface is finely punctate. 



68. Eurytoma fusca, new species 



Map 30 



Female: Black. Length averages 2.1 mm. (1.8-2.9); abdomen 

 plump; oval from a lateral view and with some lateral compression; 

 length averages 1.4 mm. (1.2-1.6); sixth abdominal segment at 

 longest point averages .47 mm. (.40-.55) ; fine pitting limited to lower 

 anterior quarter of lateral surface of sixth; surface of rest of segment 

 smooth; ninth abdominal segment short but sharply pointed, averaging 

 in length .15 mm. (.12-.17). Internal geintalia short and weakly 

 developed dorsaUy, anteriorly; dorsal valves narrow for horizontal 

 length and bend dorsally at less than a right angle anteriorly; stylet 

 arch in an oblique plane but only a little above a horizontal plane; 

 whole structure averages 1.4 mm. in length, .73 mm. in height, and 

 expanded dorsal extension of ventral valves averages .12 mm. in width. 

 Propodeum only slightly depressed to flat; median furrow absent or 

 indicated in upper one-half only; surface finely punctate; slightly 

 arched dorsal carinae curves ventrally for about one-third length of 

 propodeum and then fades out or turns laterally. Scape of antenna 

 most often with outer face black to dark brown, except yellowish- 

 brown base; less often lower half yellowish brown; rest black to dark 

 brown; segments of flagellum slightly longer than wide; first the 

 longest, two to five about equal, six to eight closely fused as a terminal 

 unit. Legs most often with black to dark brown on all femora and 

 tibiae; knees and apices yellowish brown; less often foretibiae all 

 yellowish brown. Tegula often deep reddish brown. Wing veins 

 straw yeUow; marginal longer than postmarginal ; marginal averages 



