474 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iis 



somewhat blunt, averaging .19 mm. (.15-.25) in length. Internal 

 genitalia with the dorsal valves very narrow for horizontal length 

 and black to light reddish brown in color; dorsal and ventral valves 

 turn dorsally, anteriorly, at approximately a right angle; ventral 

 valves curve dorsally and then slightly posteriorly so that stylet arch 

 and fulcral plate are in a vertical plane; whole structure averages 

 1.6 mm. (1.2-1.9) in length and 1.0 mm. (.87-1.1) in height; height 

 averages about 64% of the length. Thorax with the tegula yellow or 

 yellowish brown; most often some deep reddish-brown coloration on 

 dorsal and lateral surface of the pronotum; less often dorsal thorax 

 black, or reddish brown extensive on both dorsal and lateral surfaces. 

 Propodeum narrowly concave; shallow concavity occupied almost 

 entirely by the median furrow that may be delimited laterally by 

 distinct, irregular carinae, or lateral carinae may lose identity in 

 lower half; median carina more or less complete to base dividing 

 furrow into small irregular rectangles, largest at top, smallest toward 

 base; median carinae may separate deep rectangular depression below 

 base of median furrow into two foveae; lateral areas narrow and ir- 

 regularly ridged and pitted. Head most often black, occasionally 

 deep reddish brown frons; fine striae on face converging on the 

 clypeus. Antenna with the scape yellow; flagellum appears six 

 jointed; segments longer than wide. Legs yellow including coxae. 

 Wing veins yellow; marginal mediumly broad and stout and averages 

 .32 mm. (.32-.37) in length; postmarginal linear, short, and averages 

 .15 mm. (.15-. 17) in length; thus the marginal is quite often twice 

 the length of the postmarginal; stigmal vein short and club deeply 

 rounded so that it appears almost square. 



Male: Black or mostly reddish brown. Averages 2.6 mm. (2.3- 

 3.0) in length. Thorax and abdomen most often black, or reddish- 

 brown tinge to lateral pronotum and occasionally to dorsal pronotum 

 and lower, lateral meso- and metanotum; may be a deep reddish- 

 brown splotch on the lateral aspect of sixth abdominal segment. 

 Head often black, or it may have a reddish-brown frons. Petiole 

 longer than hindcoxa by about Iji times; most often black but may 

 be reddish brown. Legs and all coxae yellow or hindcoxae may be 

 black to dark reddish brown. Tegula yellow. Antenna with the 

 scape yellow; flagellum appears 7-segmented. Wing veins with same 

 relationships as in the female. 



Types: U.S. National Museum, no. 1531, 1 female and 4 males, 

 labelled by A. Bolter, 1890. 



Type locality: No locality is given for the types but Walsh de- 

 scribed many of his species from material collected in the vicinity of 

 Rock Island, 111. Lacking any specific evidence otherwise, it seems 



