452 



THE NATIONAL GEOGRAPHIC MAGAZINE 



FivY LARVv^3 AND PTJPJE IN WASTE) PAPER ( ASH-PIT REFUSE), 

 NATURAL, SIZE 



Photographs b}' Robert Newstead; by courtesy of the Liverpool 

 School of Tropical Medicine 



Egg of house-fly greatly en- 

 larged, showing the seg- 

 ments of the larvae through 

 the cuticle 



PRIVY VAULTS, SWARMING WITH FUES, ADJOINING KITCHEN DOOR 



These conditions, inviting disease and insuring the pollution of food, are practically duplicated 

 in hundreds of towns besides Pittsburg, in which this photograph was taken 



