302 THE RELATION OF FLIES TO MYIASLS 



The Blow-flies and Blue- or Green-bottle flies, CaUiphora 



spp., Lucilia spp. and Sarcophaga spp. 

 Muscina stabulans. 



The Root Maggot fly, Anthomyia radicum. 

 The Cheese Maggot fly, Piophila casei. 

 The Drone fly, Eristalis tenax. 

 Thereva sp. 



The House-fly, Musca domestica. 



In view of the abundance of this species and its habits it 

 is somewhat remarkable that it has not been more frequently 

 recorded in cases of intestinal myiasis. Austen states that only 

 two cases have been brought to his notice ; in both cases the 

 larvae occurred in infants. In one case, the larvae of Musca 

 domestica were "voided from the alimentary canal of a male infant 

 aged seven months " together with the larvae of Fannia cani- 

 cidaris. The larvae were of different ages. Larvae of M. domestica 

 have been found by me (1909) in the stools of a child. Cohn 

 (1898) also records the occurrence of the eggs in like material. 

 Nicholson (1910) records three cases of intestinal rectal myiasis ^ 



The Lesser House-fly, Fannia canicularis, and 

 the Latrine fly, F. scalaris. 



These two species would appear to be most common in cases of 

 myiasis of the intestinal and urinary tracts. As long ago as 1839 

 Jenyns recorded the case of a clergyman about 70 years of age, 

 who complained of general feebleness, loss of apjDetite and a 

 disagreeable epigastric feeling of a tremulous character. These 

 symptoms began in the spring of 1836 and it was not until the 

 autumn that the larvae were observed. They were expelled 

 repeatedly in large numbers and their expulsion in this manner 

 continued for several months. The larvae were about equal in 

 size and extremely active on their appearance. The malady did 



1 Felt (1913) records a case of myiasis caused by the larvae of M. domestica. 

 The infestation presumably arose from canned sardines which had j)robably been 

 left exposed, as eggs and larvae were found in the fish of four out of six boxes 

 examined. 



Jones (1913) describes the occurrence of twenty to thirty living larvae of M. 

 domextica in the stomach of a fatal case of hepatic abscess. The disease and the 

 occurrence of the larvae was no doubt a coincidence. 



