DIPTERA. 483 



their yyings arc transparent; and their legs are short, and have 

 a broad whitish ring around them. The length of their body 

 rarely exceeds one tenth of an inch. They begin to appear 

 in May, and continue about six weeks, after which they are no 

 more seen. They are followed, however, by swarms of midges, 

 or sand-flies (Simulium nocivum), called no-see-'em, by the In- 

 dians of Maine, on account of their minuteness. So small 

 are they, that they would hardly be perceived, were it not for 

 their wings, which are of a whitish color, mottled with black. 

 Towards evening these winged atoms come forth, and creep 

 under the clothes of the inhabitants, and by their bites produce 

 an intolerable irritation, and a momentary smarting, compared* 

 to that caused by sparks of fire. They do not draw blood, 

 and no swelling follows their attacks. They are most trouble- 

 some during the months of July and August. 



The most common of our large gad-flies, or horse-flies, ap- 

 pears to be the Tabanus atratus, of Fabricius. It is of a black 

 color, and the back is covered with a whitish bloom, like a 

 plum. The eyes are very large, and almost meet on the top 

 of the head; they are of a shining purple-black or bronzed 

 black color, with a narrow jet black band across the middle, 

 and a broad band of the same hue on the lower part. The 

 body of this fly is seven eighths of an inch or more in length, 

 and the wings expand nearly two inches. The Tabanus cinc- 

 tus, of Fabricius, or orange-belted horse-fly, is not so common, 

 and is rather smaller. It is also black, except the first three 

 rings of the hind body, which are orange-colored. The most 

 common of our smaller horse-flies is the Tabanus lineola, so 

 named, by Fabricius, because it has a whitish line along the 

 top of the hind body. Besides these flies, we have several 

 more kinds of Tabanus, some of which do not appear to have 

 been described. These blood-thirsty insects begin to appear 

 towards the end of June, and continue through the summer, 

 sorely tormenting both horses and cattle with their sharp bites. 

 Their proboscis, though not usually very long, is armed with 

 six stiff", and exceedingly sharp needles, wherewith they easily 



♦ See Gosse's •' Canadian Naturalist," p. 100. 



