18 PROCEEDINGS OF THE NATIONAL MUSEUM Vol. 6S 



to cover most of the second and third principal segments. Some- 

 times the median black stripe is absent. 



Male. — Last genital segment varying from red to black, the pos- 

 terior forceps yellow, shining, apparently united, ending in a sharp 

 point; outer forceps of the same color, rounded at tip, straight. 

 Margin of last genital segment thin and shining yellow, projecting 

 about as far as the tips of the posterior forceps in a broad lobe; 

 penis longer than usual, slender in the middle, enlarged apically; 

 fifth sternite so retracted as to be practically invisible. 



Female. — The first principal segment of the abdomen bears four 

 bristles on the hind edge where the corners come together at the 

 middle of the venter, the second segment on the median ventral 

 portion has a transverse protuberance somewhat arcuated, bearing 

 numerous, very short, stiff spines. The third segment has an oval 

 basin-shaped concavity on the middle ventral line into which the 

 hook folds; the fifth apparent segment of the abdomen is elongated 

 and conical, covered with short, retrorse hairs; the terminal genital 

 segment is small, composed chiefly of the elongated hooks, which are 

 unsymmetrical in shape, the left one being strongly constricted at 

 the base, bulging beyond this region; the right one is stout at the 

 base and the cavity which ordinarily lies in a symmetrical position 

 between the two hooks is in this case thrown up along the side of 

 the larger hook. Townsend's type specimen and one from Southern 

 Pines, North Carolina, are the only females we possess that have 

 two hooks; 15 other females differ only in having the left hook 

 broken off at the base, the fractured portion is exceedingly slender 

 and lies along the edge of the median cavity, the stinglike ovipositor 

 so characteristic of this group lies in a groove along the side of the 

 remaining, or right-hand hook. 



Length, 5.5 to 8 mm. 



Redescribed from 46 specimens (29 males, 17 females). H. J. 

 Reinhard collected 20 males and 12 females at College Station, 

 Texas, and this lot enabled me to feel certain that the two sexes 

 belong together. In Professor Melander's collection are 2 males 

 from Wawawai, Washington, collected by him. 



In the Kansas collection are 3 males from Santa Rita ]Mountains, 

 Arizona (Snow). 



The remainder are in the National Museum as follows: 1 female 

 with both hooks, the type, collected by Townsend at Head of Rio 

 Piedras Verdes, Sierra Madre, Chihuahua, INIexico; 1 female, with 

 both hooks. Southern Pines, North Carolina (Manee) ; 2 females, 

 Claremont, California (Baker) ; 1 male, 1 female, Moscow, Idaho 

 (Aldrich) ; 1 male, Lewiston, Idaho (Aldrich) ; 1 male, DevilV 

 River, Texas (Bishopp) ; 1 male, Kerrville, Texas (Pratt). 



