395 



of all tarsi brown, all tarsi from apices of second joint obscured with 

 brown. Wings clear, cross vein distinctly infuscated. Halteres yellow. 



Male. — Antenna as long as head and thorax together, basal joint 

 much swollen, last joint about one and a half times as long as rest of 

 flagellum, plumes very long and dense. Mesonotum almost bare, the 

 hairs between vittse very w'eak ; a small group of rather short hairs 

 close in front of wing-base. Abdomen with quite long and rather 

 numerous pale hairs; hypopygium as in Figure 6, Plate XXVITI. Legs 

 rather slender and without long hairs; basal joint of fore tarsus about 

 two thirds as long as fore tibia and distinctly longer than the remain- 

 ing joints combined; fourth tarsal joint of all legs obcordate. Wing 

 venation as in j'jreceding species. 



Female. — Structurally almost identical with the female of the pre- 

 ceding species. 



Length, 4.5-5 mm. 



Illinois localities: L^^rbana, July 2, 1887 (C. A. Hart), and Sep- 

 tember 5. 19 14 (J. R. Malloch) ; Havana, August and September, sev- 

 eral of the speciments at light. Larvae occur commonly in the Illinois 

 River as far north as Ottawa, and in the numerous connected lakes. 



Originally described from Tick Island, Fla., and not subsecjuently 

 recorded as far as I am aware. 



PsiivOTANYPUs Kieffer 



As f.ar as our present knowledge goes, this genus is represented in 

 North America by only a single species, occidentalis Coquillett. The 

 immature stages are unknown. 



PSILOTANYPUS OCCIDENTALIS CoC|uillett 

 Tanypus occidentalis Coquillett, Proc. U. S. Nat. Mns., Vol. 25, 1902, p. 92. 



Male. — Brownish black, subshining. Head fuscous, including the 

 antennae and their plumes, face yellowish. Pronotum, anterior mar- 

 gins of mesonotum, upper central portion of pleur?e, and scutellum 

 vellowish. Venter of abdomen yellowish, dorsum black. Legs brown- 

 ish, tibiae and tarsi, except their apices, paler. Wings clear, veins 

 brownish. Halteres yellow. 



Pronotum rather wide, central excision weak. Hypopygium wath 

 distinct, acute extension of dorsal plate, apical portion of lateral arm 

 recurved. Legs slender, fore tarsi with moderately long sparse hairs, 

 basal joint four fifths as long as fore tibiie ; fourth tarsal joint on all 

 legs linear, longer than fifth ; pul villi absent ; empodium small. Vena- 



