FLIES. 231 



considerably in colour; some are yellow, with black bands and 

 markings, or vice versa, and F. Pellucens, Panz., is black, with a dull 

 white band at the base of the abdomen. 



The species of Eristalis, Latr., much resemble the VolnceUce, but 

 are more slender, and the abdomen is rather longer and more 

 pointed. The flies are black, or metallic green, or reddish, and 

 often varied with whitish hairs ; the wings in some species are 

 marked with a brown cloud. The larvae live on rotting animal or 

 vegetable matter, and frequently live in stagnant water. They are 

 often met with in drains, cesspools, and similar situations, and 

 are remarkable for having a very long appendage at the end of the 

 body resembling a rat's tail. 



Milesia Crabroniformis, Fabr., is a large species, common in 

 Southern Europe, with a black head and thorax, a yellow spot on 

 each shoulder, and a long yellow abdomen banded with black. It 

 sometimes measures nearly an inch in length ; its transformations 

 are unknown. 



Family XXXI. — Conopidm. 



Head large, always broader than the thorax; antennae long, 

 third joint clubbed, and ending in a bristle ; eyes not contiguous ; 

 ocelli present or absent; abdomen cylindrical, more or less con- 

 tracted at the base, and expanded behind ; legs moderately long 

 and thick ; larvae parasitic on OrtJioptera and Hymenoptera. 



The species of Conops, Linn., are black slender flies, nearly 

 half an inch long. They are marked with yellow spots and bands, 

 and have some resemblance to wasps. Myopa, Fabr., is typical of 

 another section of the family ; they are reddish-brown species 

 about a quarter or half an inch in length, with a broad depressed 

 abdomen. 



Family XXXII. — Pipunciilidce. 



Head large, round, broader than the thorax ; antennae short, 

 third joint egg-shaped, with a bristle inserted ne:..- its base; eyes 

 large, not quite contiguous in the males ; ocelli present ; abdomen 

 narrow, round, or slightly compressed ; legs with a few short 

 spines ; larvae parasitic on other insects. 



The species of the typical genus Pipicncuhis, Latr., are black or 

 dark brown insects, which swarm in shady places near hedges, 

 sometimes resting on leaves, but never on flowers. 



