THE SNIPE FLIES 



(Family Leptida.) 



These are slender, rather small flies, somewhat resembling the 

 robber flies, on account of their long legs and slender bodies. 

 They have usually smoky wings and velvety bodies, some of 

 them slightly resembling yellow-banded wasps. They are not 

 especially numerous. Some of these flies are predatory and de- 

 stroy other insects and this may be the habit of all. They are 

 sluggish in their habits and are easily caught. The larvae are 

 predaceous, and variable in their habitations. Some are found in 

 water, others live in decaying wood, or in the earth, in moss, in 

 dry sand, or in the burrows of wood-boring beetles. There is a 

 curious resemblance between the habits of the species of the 

 genus Vermileo and the well-known ant-lions, the larvae forming 

 conical pitfalls in the sand in which to catch small insects. Flies 

 of the genus Atherix lay their eggs, as do the females of the 

 Stratiomyiid genus Odontomyia, in masses on dried branches 

 overhanging the water. The masses become very large and 

 pear-shaped from the curious fact that a number of females add 

 their eggs to the same mass, frequently dying after egg laying 

 and leaving their bodies attached to the egg mass. The larvae 

 are cylindrical and sometimes bristly, and may have fleshy ap- 

 pendages resembling prolegs on the abdomen. Atherix has 

 seven pairs of these prolegs. The larva of one species has been 

 found -by Hart in damp earth. 



The families Xylophagidae and Crenomyiidae which will be 

 found mentioned in some books are merged with the Leptids. 

 The Xylophagids are rather slender flies with the abdomen 

 pointed in the female sex. The Coenomyiids on the contrary are 

 stout, rather large flies. The larvae of some of Xylophagids live 

 under bark and prey on other insects and the larvae of Coenomyia 

 live in the earth and are also probably predaceous. 



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