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] 
DIPTERA. _ tg 
So far as known the adults never exhibit the bloodthirsty propensi- 
ties of their Southern cousins. 
Simulium canescens Bremi. 
This species has been studied by Kolliker, according to a citation of 
Osten Sacken (American Entomologist, Vol. I], p. 231), 
Simulium rivulare Planch. 
Cited by Osten Sacken (American Entomologist, Vol. II, p. 231). It 
does not appear that it is discussed from an economic standpoint. 
Simulium sp. 
A species of Simulium is said to be a serious pest in Brazil. It was 
first technically discussed by Pohl and Kollar. 
Simulium venustum Say. 
In 1823 Thomas Say described in a paper entitled ‘“‘ Descriptions of 
dipterous insects of the United States” a number of Diptera which he 
says were collected chiefly during the expedition to the Rocky Moun- 
tains under the command of Major Long. Among the rest is the 
description of the present species and the followin note: ‘This very 
pretty species perched in considerable numbers on our boat at Ship- 
pingsport, Falls of the Ohio. It ran with considerable rapidity, con- 
stantly advancing its long anterior feet. Its bite is pungent.” 
While very probably one of the forms included under the general 
head of buffalo-gnats of the Mississippi Valley no further records of 
its especial attacks are known, and nothing is known as to the larval 
form from which it develops. Shippingsport does not appear on pres- 
ent maps, but the “ Falls of the Ohio”-lie between Louisville, Ky., and 
Jeffersonville, Ind., and since some of these species are peculiarly local 
in their distribution, it would be courting success to search for the larvie 
in the rapids of the river at that point. 
Say’s description of the adult form is as follows: 
Black; thorax, two perlaceous spots before and a larger one behind; poisers black, 
capitulum bright yellow, dilated. 
Inhabits Shippingsport. 
Body black; wings whitish, with yellow and iridescent reflections. 
Male, eyes very large, separated only by a simple line, dull reddish yellow, inferior 
half black; thorax velvet-black, a bright oblique, perlaceous, dilated line each side 
before, and a large perlaceous spot or band behind; sides beneath varied with per- 
laceous; feet, tibia above, and first joint of the four posterior tarsi white; abdomen 
with an oblique perlaceous line at base, and two approximate, lateral, perlaceous 
ones near the tip. 
Female, eyes moderate; thorax plumbeous-black, immaculate; scutel black; abdo- 
men whitish beneath. 
