» 



488 INSECTS INJURIOUS TO VEGETATION. 



which they thrust out of the water in order to breathe. The 

 skin of these larvEE is merely shortened a little, without wholly 

 losing its former shape, when the inclosed insects change to 

 pupae; thereby showing 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 pupae. Some of the soldier-flies ( Stratyo- 

 mys) have a broad oval body, ornamented with yellow ti'iangles 

 or crescents on each side of the back, and their antennae are 

 somewhat like those of Midas and of the gad-flies ; others ( Sar- 

 ins) are slender, often of a brilliant brassy green color, with a 

 bristle on the tip of their antennas. The maggots of the latter 

 live in rich mould. 



The Syrphians (Syrphid^) have a fleshy, large-lipped pro- 

 boscis, elbowed near the base, and enclosing only four slender 

 bristles. They live on the honey of flowers. The last joint 

 of their short antennae bears a bristle, which is sometimes 

 feathered. Their heads are large and hemispherical. Many 

 of these flies are often mistaken for bees or wasps, and some 

 of them lay their eggs in the nests of the insects they so closely 

 resemble. Others drop their eggs among plant-lice, which 

 their young afterwards destroy in great numbers. The larvae 

 of a few are aquatic, and are provided with very long, tubular 

 tails, through which they breathe, and have been called rat- 

 tailed maggots. Some of the largest and most beautiful of 

 these flies live, in the maggot state, in rotten wood. One of 

 these rat-tailed flies is often seen on windows, in the autumn. 

 It flies with a buzzing noise. Its eyes are very large, and of a 

 bright copper-color; its body is brassy green; and there are 

 five gray stripes on the thorax. It measures about four tenths 

 of an inch in length. It is the Eristalis sincerus of my " Cat- 

 alogue." The Milesia excentrica, named in the same work, 

 strikingly resembles a hornet; its hind body being banded 

 with black and yellow in the same way. Its head and thorax 

 are black, the former margined around the eyes, and the latter 

 spotted, with yellowish white. The legs are ochre-yellow, 

 except the shanks and feet of the first pair, which are black. 

 Its body measures nearly three quarters of an inch in length. 



