40 THE HOUSE FLY— DISEASE CARRIER 



as an average, since no larvae are found in perhaps the 

 greater part of ordinary horse manure piles. Neither, 

 however, does it show the limit of what can be found, 

 since on the same date about 200 puparia were found 

 in less than one cubic inch of manure taken from a spot 

 two inches below the surface of the pile where the lar- 

 vae had congregated in very great numbers. This, as 

 stated, was in August and the height of the fly season 

 had not yet been reached. Major N. Faichnie, of the 

 Royal Medical Corps, in the Journal of the Royal Med- 

 ical Corps for November, 1909, gives the result of cer- 

 tain experiments with flies, indicating that in India he 

 reared 4,000 flies from one-sixth of a cubic foot of 

 trench ground. He also states that he reared 500 

 flies from one dropping of human excreta. 



Further counts have been made by Dr. W. B. Herms, 

 of the University of California ( 19 10) . Doctor Herms 

 took four samples from different parts of an average 

 horse manure pile in Berkeley, Cal. (not near a livery 

 stable). The four samples weighed fifteen pounds in 

 all and contained by actual count 10,282 larvae, nearly 

 all of which were nearly or quite full grown. The 

 weight of the entire manure pile w^as estimated at 

 1,000 pounds, and, at the rate counted, estimating that 

 possibly one-third of the pile was uninfested, the pile 

 contained 455,000 and more larvae. Is it any wonder 

 that flies swarm near the average stable? 



