Diptera 



263 



more hairy species {Volucella and Eristalis) are strikingly like wasps 

 and bees. The head is large with very well-developed eyes ; the 

 mandibles and first maxilla; are present as stylets, and the sucker is 

 fairly prominent. The larvz, which have no distinct head-capsule, 

 vary much in their outward form and manner of life. Some (Syrfhus) 

 are fairly active, 

 tapering grubs, liv- 

 ing openly on plants 

 and preying on 

 aphids; others 

 (^Eristalis) are 

 cylindrical maggots 

 with sucker feet, 

 feeding on organic 

 matter in foul water, ^ 



andbreathing 

 through a single 

 spiracle situated at 

 the tip of a long 

 telescopic "tail"; 

 others ( Volucella) 

 are short maggots <0^!fy\ 

 with pointed , i4§fef^ 

 tubercles on the seg- /^^-"rjs 

 ments, living in the ^\^.'c^ 

 nests of wasps and 

 bees where they act c^ 

 as scaveng ers or 

 prey on the Hymen- 

 opterous grubs ; 

 others again 

 ( Cheilosia) feed in 

 fungi or decaying 

 vegetable matter. 

 The family is v e r y 

 numerous in genera 

 and species, and 

 world-wide in its 

 rani;e. 



Conopidae.— The 

 Conoputa: are another 

 family of brightly- 

 coloured wasp - like 

 flies distinguished by 

 the very large swol- 

 len head, thin horny sucker, and total absence of large bristles on the 

 hind-body segments. The members of one sub-family {Conopina:) have 

 the antennal segments long and straight with a jointed claw at the tip of 



;. 145. — /. Warble-fly {Hypodervia bovis, D.G.), 

 twice nrUural size ; a. egg, magnified 20 times ; d. 

 newly-hatched larva, magnified ; /'._ full-grown 

 larva, twice natural size ; e. its anal spiracles, more 

 highly magnified ; c. puparium, slightly enlarged. 

 From Riley (after Brauer), Insect Life, vol. 2 

 (U.S. Dept. Agr.). 



