408 INSECTS INJURIOUS TO VEGETATION. 



by Mr. Say, in the Appendix to Keating^s "Narrative," and in 

 the second volume of the " American Entomology," where it is 

 figured. The generical name, signifying a common fly, is rather 

 unfortunate, for this is a rare insect. The only specimens known 

 to Mr. Say were found by him in a small forest of scattered trees, 

 on the Pecktannos river, in Wisconsin Territory. A few have 

 been taken in Massachusetts, one of them on Blue Hill, in Mil- 

 ton ; and Mr. Gosse found three specimens, in as many years, in 

 Canada. In its transformations this insect is more nearly related 

 to the gad-flies and the Asilians than to the soldier-flies, near 

 which it has generally been placed ; though it approaches the 

 latter in its structure, and in its sluggish habits. The larvee or 

 maggots, though not yet discovered, undoubtedly live 'in the 

 ground, or in decayed vegetable substances, like those of the 

 horse-flies and other predatory insects ; for Mr. Gosse found 

 one of his specimens, on the grass, in the act of emerging from 

 the pupa-skin. He has also figured* the pupa, which is of a 

 chestnut-brown color, and has transverse rows of spines on the 

 abdominal rings. 



Most of the soldier-flies (STRATiOMYADiE) are armed with 

 two thorns or sharp spines on the hinder part of the thorax. 

 They form the first family of the flies that undergo their transfor- 

 mations within the hardened skin of the la-rva, which is not thrown 

 off till they break through it to come out in the winged state. 

 Their proboscis contains, at most, only four bristles, is not fitted 

 for piercing, but ends with large fleshy lips, by means whereof 

 these flies suck the sweet juices of flowers. Most of them are 

 found in wet places, where their larvae live ; some of the latter be- 

 ing provided with a lube, in the hinder extremity, which they 

 thrust out of the water in order to breathe. The skin of these 

 larvas is merely shortened a little, without wholly losing its former 

 shape, when the inclosed insects change to pupae ; thereby show- 

 ing that this family is truly intermediate between the preceding 

 flies, which cast off their larva-skins, and those which retain them, 

 and take an oblong oval shape, when they become pupas. Some 

 of the soldier-flies {Stratyomijs) have a broad oval body, orna- 



* " Canadian Naturalist." p. 199. 



