219 



hairs on the disc, each of which appears to have a minute 

 l)r()\vn s])()t at its base; scutclluni with short bristles on the 

 ])osterior margin, the disc with weak hairs, outline of 

 scutellum rounded, its len<ifth equal to about one third of its 

 breadth. Alxlomen cl()n<?ate, narrow. Legs long, the fore 

 and hind femora slightly thicker than the mid pair; fore 

 femora with about 10-12 short black thorns on the apical 

 half of their ventral surfaces ; mid and hind femora each with 

 but one discernible bristle on the antero-ventral surface near 

 to the apex ; hind tibia straight, slightly shorter than the 

 femur; hind tarsus slightly longer than the tibia, basal 

 joint slightly longer than the remaining joints together; 

 second joint barely more than a third as long as first and 

 about two and a half times as long as third ; claws elongate, 

 subequal, toothed near the base. Wing with, third vein 

 almost seven eighths the distance to the apex; fourth vein 

 very indistinct, the fork apparently just before the cross 

 vein; costa almost bare. Length, 4 mm. . . . Illinois ensis, n. sp. 



Locality, Algonquin, 111., May 25, 1894 (Nason). One specimen. 



Halteres yellow 8 



Hind tarsal claws very unequal in size. 



Female. — Black, body highly polished. Legs yellow, apices of 

 femora, of tibiae, and of first three tarsal joints, and whole 

 of last two tarsal joints black-brown. Femora slender, the 

 fore and mid pairs unarmed, the hind pair with two thorns 

 on the under side near to apex. Fourth vein forking a short 

 distance before the cross vein. Length, 3 mm. (B. C.) .... 

 curriei Coquillett. 



I have not seen this species. The above abridged description 

 is from Coquillett 's original definition of the species. 

 Hind tarsal claws subequal in length. 



3Iale. — Black-brown, subshining. Head brown ; antennae 

 brown, paler at the base, the hairs brown. Mesonotum very 

 similar to that of iUinoisensis in coloration and markings, 

 but the pollinosity is not so dense, the vittae are not so 

 clearly defined, and there are fewer and larger brown spots 

 on the disc because of the sparseness of the hairs; the 

 scutellum is generally yellowish. The abdomen is brown, 

 slightly shining, with slight pollinosity. Legs yellow; coxae 

 brouni ; all femora brown except the bases and a band at 

 apices, the hind pair very obscurely pale at apices ; tibiae 

 either brownish at bases and apices or entirely brownish, the 

 hind pair most distinctly broAvned; apices of all tarsal 

 joints narrowly browned. Wings clear, veins brown. 



Length of antenna slightly exceeding that of head and thorax 

 together. Eyes narrowly separated ; proboscis less than half 

 as long as height of head. IMesonotum with the hairs slightly 



