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FAMILY SYRPHID^. 

 (Hover Flies.) 



Many of these flies are brightly coloured, some 

 seem to mimic wasp or bees. The syrphid flies poise 

 seemingly motionless over flowers, hence are termed 

 "hover flies. " This motionless appearance is due to 

 the rapidity of the vibrations of the wings. They 

 are seen hovering over flowers or leaves, either sip- 

 ping the nectar of flowers, or the mother-insect is 

 laying eggs on plants where aphides are present. 



The larva (Plate 43, Fig. 3) is a long grub without 

 legs, but there are lateral projections of the body 

 wliich enable it to hold on or more forward, and 

 usually there is a strong anal segment by means 

 of which it clings to the leaf. The ** mouth*' is 

 in the form of a proboscis, very elongate, which can 

 be pushed out and then withdrawn. We watched 

 the syrphid larv^ feeding on aphides on the wild 

 cotton plant {Gomphocarpits). The larva or grub 

 looked like an elephant in the way it thrust out its 

 long trunk and ''spiked" an aphis. 



The pupa (Plate 43, Fig. 2) is not free, but is en- 

 closed in a larval skin or puparium, which in most 

 cases is intermediate between the seed-like puparium 

 of the house fly and that of the soldier fly, whose 

 puparium retains its larval form. The syrphid 

 puparium is broad at the apex and tapers toward 

 the point of attachment. With a lens one can see 

 the spine-like tubercles which had been present in 

 the larva, and though the pupa is somewhat seed- 

 like in appearance it is not smooth and rounded like 

 that of the muscid flies (house flies, blow flies). 



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