BLOW FLIES 



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morsitans transmits the cattle trypanosome disease, nagana and the human infection 

 due to Trypanosoma rhodesiense. 



Auchmeromyia luteola. This is an African fly, the larva of which is known as 

 the " Congo floor maggot,' ' and is a blood sucker. The larva is of a dirty- white color 

 and about 2/3 of an inch long. It crawls out at night and feeds on the sleeping 

 natives. This is the only known instance of a blood-sucking larva. 



Calliphora vomitoria and Lucilia caesar. These are flies with brilliant metallic- 

 colored abdomens, commonly called blow flies in the case of Calliphora and blue- 

 bottle flies for Lucilia. They deposit their eggs on tainted meat and in wounds. 



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FIG. 87. Insects in which the larval stage is important, (i) Chrysomyia 

 macellaria; (2) C. larva; (3) Dermatobia cyaniventris larva, early stage (ver ma- 

 caque); (4) D. cyaniventris larva, later stage (torcel or berne); (5) D. cyaniventris; 

 (6) Auchmeromyia luteola; (7) A. luteola, larva; (8) Sarcophaga magnifica; (9) 

 S. magnifica larva; (10) Anthomyia pluvialis; (n) A. pluvialis larva. 







Many cases of obscure abdominal trouble are probably due to the larvae of these 

 flies. Intestinal myiasis is undoubtedly of greater importance than has been 

 thought. The larvae, with hook-like projections anteriorly and a ringed body, can 

 easily be recognized in the faeces. They have been mistaken for flukes. They 

 also have a tendency to be attracted by those with ozena and the larvae may develop 

 in the nostrils. 



Chrysomyia macellaria. This is known as the screw-worm when in the larval 

 stage. The adult fly resembles the blue-bottle flies. It is distinguished from them, 

 however, by the presence of black stripes on thorax. These flies are very common 

 over nearly all North and South America. The thorax is striped. The eggs, which 



