Insecutor Inscitiae Menstruus 



Vol. II DECEMBER, 1914 No. 12 



NEW DATA AND SPECIES IN SIMULIIDi^: 



{Diptera) 

 By FREDERICK KNAB 



The theory that Simuliidae are the agents for transmitting pellagra has 

 awakened wide interest in this group of blood-sucking flies and has caused 

 them to be more extensively investigated. Gsnsiderable advance has 

 been made in our knowledge of the group systematically, but much yet 

 remains to be learned. Contributions, under existing circumstances, must 

 be necessarily fragmentary, but it is hoped that such will lead to a revi- 

 sion of revisions. 



Simulium pulverulentum, new species. 



Female : Occiput, frons, and face gray pruinose ; frons broad above, 

 greatly narrowed to neau: the antennae. Antennae short, the two basal 

 joints dull ferruginous yellow, the others blackish, clothed with paJe 

 pubescence, the t^ pointed. Scutum almost uniformly blackish with gray 

 pruinosity, an ill-defined, straiight, median black line extending the entire 

 length, cind outwardly broader, hardly perceptible, sinuate stripes of the 

 usual conformation ; vestiture of small, hair-like silvery scales, rather dense 

 and nearly uniformly distributed. Scutellum broad, short, bluntly rounded, 

 concolorous with the mesonotum and with longer, transversely directed, 

 silvery hair-like scales. Postnotum blackish. Pleurae dark gray pruinose, 

 the pteropleurae paler. Abdomen subcylindrical, dull black, without 

 marked plications, the basal segment paler. Legs black and white, the 

 small, appressed hair-scales on femora amd tibiae pale and shining; einte- 

 rior coxae, trochanters, and bases of all the femora dull ferruginous yellow ; 

 anterior tibiae white on the basal two-thirds, a blackish ring close to base, 

 the tarsi wholly black and with the first joint long and rather slender ; 



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