510 



■FLY MAGGOTS AND MYIASIS 



the characters used in distinguishing genera and species of fly 

 maggots. A few t^'pical forms are shown in Fig. 243. 



It is more convenient to consider the different types of myiasis 

 according to the way in which the larvae attack tlie body or ao- 

 conhng to parts affected than according to the famihes and genera 

 to whicli the flies belong. We may divide the various flies 



5tomo*/a ca Icltrans (x 75) 



Calliphora vomitoria «50) 



Uucllla caeaarwso) 



Musca domcsticaCA/S) 



Muaclna stabulans(^7i) 



Cochllomyio r/iaccl'arinCX60) 



flancophagq ^arracemae.cxSO) 



(Sostrophiluj 9pr(x2f) 



Oestrus ovis i/io'. 



Fio. 243. Posterior stigmata and breathing pores of various maggots. Note 

 distance apart of opposite stigmal plates, form and position of spiracles, pres- 

 ence or absence of button, etc. 



causing myiasis into four groups: (a) those in which the larva hve 

 outside the body and suck l)lood by pmicturing the skin, (6) 

 those in which the Uirvie develop under the skin; (c) those in 

 which the eggs or young larva' are deposited in wounds or in 

 natural cavities of the body, such as the nose, ears and vagina; 

 and (d) those which liv(> in or pass through the intestine or uri- 

 nary passages. 



