16 THE HOUSE FLY DISEASE CARRIER 



pidors and open snuff-boxes. The entomological world 

 has accepted the statement, with, however, some doubt 

 as to the snuff-boxes. Prof. S. A. Forbes, however, 

 informs the writer that August 22, 1889, ne received 

 from an old friend, T. A. E. Holcomb, then a druggist 

 at Kensington, 111., a box of snuff containing dipterous 

 larvae. From these dipterous larvae Professor Forbes 

 bred the true house fly. His recollection of the matter 

 is very clear, and he has now in his collection a very 

 under-sized specimen labeled Musca domcstica and 

 bearing an old pencil label in his handwriting, "Snuff, 

 August 26th." 



He afterwards called upon Mr. Holcomb in his drug 

 store and learned that among his constant customers 

 were some old foreigners who came so frequently t<> 

 have their snuff-boxes filled that for convenience in 

 serving them he was accustomed to keep an open box 

 of snuff upon one of his show-cases, and from this box 

 the specimens came. 



A very important series of observations was carried 

 on under the direction of Professor Forbes in the sum- 

 mers of 1908-1909 by his assistants, Mr. A. A. Girault, 

 at Urbana, and Mr. J. J. Davis, in Chicago, for the pur- 

 pose of ascertaining exactly what other substances 

 aside from horse manure will serve as breeding places 

 for house flies. The results of these observations, not 

 previously published, have been placed at the writer's 

 disposal by Professor Forbes. They constitute a very 

 valuable addition to our knowledge on this subject. It 

 was a surprise to find that nearly a thousand flies had 



