538 PROCEEDINGS O'F THE NATIONAL MUSEUM vol. 93 



Mali . — Length, 1.1—1.2 mm. First funicle segment one-fifth longer 

 than pedicel, second, third, and fourth equal in length and each one- 

 fifth longer than first, funicle segments enlarged near bases and bearing 

 setae twice as long as segments, as in figure 16, 1; club as long as two 

 apical funicle segments; gaster equal in length to thorax. 



Type locality.— Elk Point, S. Dak. 



Types.— U.S.N.M. No. 20394. 



Hosts. — Larvae of Mordellistena pustulata Melsheimer, Mordellis- 

 tena sp., Cylindrocopturus adspersus (LeConte), and, rarely, the 

 Hessian fly, Phytophaga destructor (Say). 



Distribution. — Illinois, Iowa, Kansas, Maryland, New York, North 

 Dakota, South Dakota, Virginia. 



TETRASTICHUS WHITMANI (Girnult), new combination 



Figure 18, d 



Aprostocetus whitmani Gikattlt, Ann. Ent. Soc. Araer., vol. 9, p. 296, 1916. 

 Aprostocetus marilandicus Gibault, Ent. News, vol. 28, p. 21, 1917. (New 

 synonymy. ) 



Head and thorax black, noniridescent ; apex of abdomen and dark- 

 ened parts of legs, brown; apices of coxae, bases and apices of fore 

 and middle femora, hind femora, all tibiae, basal segments of tarsi, 

 and base of gaster light yellow or white. 



Female. — Length, 2.0 mm. All funicle segments subequal in length ; 

 apex of scape reaching level of dorsal margin of anterior ocellus; 

 length of malar space one-half height of compound eye. Mesopraescu- 

 tum with one bristle at each lateral margin ; submarginal vein of fore- 

 wing with one dorsal bristle; apex of hindwing acute. Surface of 

 propodeum shagreened ; paraspiracular carinae present ; mesal length 

 of propodeum one-sixth length of mesoscutellum ; gaster one and three- 

 quarters times as long as thorax. 



Male. — Length, 1.8 mm. First and second funicle segments equal 

 and each slightly shorter than third segment, third and fourth equal, 

 funicle segments semiquadrate and without long setae, as in figure 16, // 

 gaster equal in length to thorax. 



Type locality. — St. Paul, Minn. 



Types.— U.S.N.M. No. 19936. 



Host. — Eggs of leaf beetle, Physonotaunipunctata (Say). 



Distribution. — Maryland, Minnesota, South Dakota. 



Remarks. — The characters of the male antennae show conclusively 

 that this species and ainsliei Gahan are different; the differentiation of 

 the females is, however, quite difficult. 



