4 8 



Insects and Disease 



Many cases are recorded of these flies laying 

 their eggs in the ears or nose of children or of per- 

 sons sleeping out of doors during the day. Espe- 

 cially is this apt to occur if there are offensive dis- 

 charges which attract the fly. In such cases the 

 larvae burrow into the surrounding tissues, de- 

 vouring the mucous membranes, the muscles and 

 even the bones, causing terrible suffering and 

 usually, death. The larvae in such situations may 

 be killed with chloroform and, if the case is at- 

 tended to before they have destroyed too much of 

 the tissues, recovery usually occurs. 



The blow-flies (Fig. 26) (Calliphora vomitoria) 

 and the bluebottle flies (Fig. 27), (Lucilia spp.) 

 and the flesh-flies (Fig. 28) (Sarcophaga spp.) all 

 have habits somewhat like the screw-worm fly. 

 Any of them may lay their eggs in wounds on man 

 or animals with the same serious results. 



The flesh-fly instead of laying eggs deposits the 

 living larvae upon meat wherever it is accessible, 

 and as these develop with astonishing rapidity they 

 are able to consume large quantities of flesh in a 

 remarkably short time. In this way they may be 

 of some importance as scavengers, but it is better 

 to get rid of the waste in other ways than to leave 

 it for a breeding-place for flies that are capable of 

 causing so much damage and suffering. 



