220 



longer and more sparse than in illinoisensis. Abdomen 

 rather broad for a male, the sides subparallel, second segment 

 elongated ; hypopygium protruding as far as the combined 

 length of the last two segments; lamellfe symmetrical. Legs 

 long ; fore femora slightly stronger than the other pairs ; 

 fore femora with 6-8, mid femora with 3-5, hind femora 

 with 5-7 thornlike bristles, all on the apical half of the 

 antero- ventral surface, the postero-ventral surface without 

 distinct bristles; all legs with short hairs on the whole of 

 their surfaces, those on the antero-dorsal surface of the hind 

 tibia and the dorsal surface of the hind tarsus elongate ; hind 

 tibia straight ; hind tarsus longer than the tibia by at least 

 the length of the last two joints, basal joint exceeding in 

 length the next three joints together, fourth joint half as 

 long as fifth ; claws on all legs subequal, rather stout, and of 

 moderate length. Third vein reaching five sixths the wing- 

 length ; fourth vein forking at the cross vein ; costa nearly 

 bare. Length, 3-3.5 mm. 



Female. — Differs from male in having the antennae short-haired; 

 the eyes are separated by a narrower line ; the mesonotum is 

 densely grayish pollinose, and the ground color, especially 

 of the scutellum and postnotum, is distinctly paler ; the 

 abdomen is also more yellowish in color, and the pollinosity 

 here is also more distinct ; the legs are colored as in the 

 male, but the two types of markings are very distinct, those 

 with the brown hind tibia; having also the anterior pairs 

 similarly colored, the brown on the other parts of the legs 

 more intense, and the face blackish ; the legs are stronger 

 than in the male, the thorns on the femora are not in a 

 single row, but irregularly arranged and occupying the 

 antero- ventral surface from middle to apex; the last tarsal 

 joint has distinct long spines on the ventral surface; the 

 claws are subequal, strong, and very long; the third vein 

 extends at least nine tenths of the distance to the apex of 

 wing (PI. XIII, Fig. 6). Length, 4-5 mm. 



This species was originally described by Loew from examples 

 obtained from Pennsylvania, and has since been recorded 

 from New Jersey by Smith. In the collection here, there are 

 specimens from Algonquin and Havana, Illinois. Though 

 the presence or absence of the spines on the ventral surface 

 of the last tarsal joint has generally been considered as of 

 specific value, and in some cases of generic importance, it is 

 quite clear that the sexes here described belong to one species. 

 In one lot of examples, reared from pupae bearing the same 

 data, a considerable number of both sexes occur, agreeing 

 with the characters given, but I have failed to find in it a 

 single male that has the two rows of ventral bristles on the 



