THE SYRPHIAXS. 609 



slender bristles. They live on the honey of flowers. The 

 last joint of their short antennae hears a bristle, which is 

 sometimes feathered. Their heads are large and hemi- 

 spherical. 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 Iarva3 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 6 of my Cata- 

 logue. The Milesia excentrica 7 

 (Fig. 267), 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 



[6 Eristalis sincerus, Harris, is identical with E. ceneus, Linn., so common in 

 Europe. OSTEN SACKEX.] 



[ " The description of this species is too short to have a scientific value. In 

 order to prevent its being superseded by a subsequent description, under some 

 Other name, I subjoin a full description. 



Milesia excentrica, Harris. Thorace nigro, flavomaculato, scutello ceneo; ab- 

 domine flavo, nigro fasciato; pedibus fulvis; tibiis, tarsisque anticis nigris; 

 Length, -fa to ^ inch. 



Male : Hypostoma golden-yellow, sericeous, with a shining black stripe in the 

 middle. Antennas pale ferruginous; the space between the eyes has the form of a 

 triangle, which is golden-yellow at the tip, and black on the vertex. The hind 

 part of the head is sericeous, yellow along the borders. Thorax black ; a yellow 

 spot on the shoulder, another behind it, from which runs a narrow groove, yellow 

 at the bottom ; a third yellow, elongated spot, pointed upwards, near the corner of 

 the scutellum. A gray stripe runs along the middle of the thorax ; it becomes 

 very faint beyond the centre and ends in a triangular yellowish spot near the cw- 

 77 



