194 



THE LESSER HOUSE-FLY AND THE LATRINE FLY 



in September 1905 and noticed its similarity to Swammerdam's 

 Latrine Larva. 



The larvae emerge as early as eighteen hours after the depo- 

 sition of the eggs, and become full-gl•o^v^l in six to twelve days. 



^^-^ois^p^^ 



% t 



-^W^ 



Fig. 87. Larva of Latrine Flj, Fannia scalaris Fab. x 12. 



The shortest time which I have recorded for the pupal stage 

 was nine days, which was in the month of August, but I believe 

 that, under very favourable conditions, the pupal stage would be 

 passed in a shorter time. 



