500 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



widest point, which is just behind the spiracles; spiracles barely 

 reaching lateral margin; sides convex, slightly wavy, apex narrowly 

 truncate ; mandibles oblique with a strong tooth on the- inner apical 

 angle. 



Type— Cat. No. 13702, U.S.N.M. 



PSEUDOXENOS FUNDATI, new species. 



Host.—Odynerus (Leionotus) fundatus Cresson, Carlinville, Illinois. 

 Described from one female collected June 25, by Charles Robertson. 



Female. — Length of cephalothorax 0.99 mm., breadth 1.18 mm., 

 breadth of head 0.91 mm., distance between mandibles 0.19 mm. 

 Cephalothorax light brown, with area in front of opening of brood 

 canal yellowish, and posterior fourth of disk lighter, margins especially 

 near middle very dark, but with a lighter round area indicating the 

 location of the spiracles. Cephalothorax convex from base, evenly 

 rounded at widest point behind spiracles; spiracles not attaining 

 lateral margin; sides sinuately oblique to the narrowly rounded apex; 

 mandibles oblique, with a sharp tooth on inner apical angle. 



Type.— Cat. No. 13703, U.S.N.M. 



PSEUDOXENOS HISTRIONIS, new species. 



Host. — Odynerus (Ancistrocerus) Tiistrio Lepeletier, Inverness, 

 Florida. Described from one female collected March 20, by Charles 

 Robertson. 



Female. — Length of cephalothorax 0.86 mm., breadth 0.89 mm., 

 breadth of head 0.76 mm., distance between mandibles 0.17 mm. 

 Cephalothorax light orange brown, with area in front of mouth yellow, 

 a brown transverse band behind the opening of the brood canal, 

 margins very dark, and remainder of disk lighter in color. Cepha- 

 lothorax rather strongly constricted at base; broadest at spiracles 

 which are laterally prominent; thence angulately convex, apex 

 evenly convex; mandibles very oblique, apically emarginate and 

 toothed on inner angle. 



Type.— Cat. No. 13704, U.S.N.M. 



PSEUDOXENOS PEDESTRIDIS, new species. 



Host. — Odynerus (Leionotus) pedestris Saussure, Carlinville, Illinois. 

 Described from one female collected July 6, by Charles Robertson. 



Female. — Length of cephalothorax 0.80 mm., breadth 0.80 mm., 

 breadth of head 0.67 mm., distance between mandibles 0.15 mm. 

 Cephalothorax light orange brown, darkest on margins and across 

 disk behind mouth in basal third, apex yellow, remainder of disk 

 orange colored. Cephalothorax not strongly constricted behind, 

 more or less evenly convex from base to apex, apex narrowly truncate ; 

 spiracles just reaching lateral margin; mandibles oblique, toothed. 



Type— Cat. No. 13705, U.S.N.M. 



