576 HOWARD 



been deposited by a person in the early stages of typhoid fever, 

 or with cholera. The flies in question might, any one of them, 

 and especially the house flies and the species under immediate 

 consideration, have flown ten or twenty feet or more to the ad- 

 joining kitchens and carried the germs direct to the food. 



There were reared from this particular mass only Sarcofhaga 

 sarraceiitcB and Homalomyia brevis. Fifty-five specimens of 

 the former species made their appearance ten days later. The 

 Sarcofhaga is not a frequent visitor to houses, but the Homa- 

 lomyia is frequently seen in human habitations. 



On June 13 a miscellaneous lot of excreta in different stages 

 was collected in south Washington and from these issued Mus- 

 cina stabidans on June 23 and 29. This was the first time we 

 had observed that the species breeds in this substance. In July 

 additional specimens were captured in an outdoor privy near 

 Washington in the District of Columbia, and at Twining City, 

 Maryland. Under similar conditions other specimens were cap- 

 tured and adults were reared from the same material. In the 

 fall series of observations of the same year, no specimens of 

 this fly were captured or bred under such conditions. 



The adult is shown in fig. 25, and the larva with anatom- 

 ical details on Plate xxx, fig. i. 



Muscina ccBsia Meig. 

 This species, found in Europe as well as in many different 

 parts of the United States, was captured upon excrement at 

 Washington, D. C. 



Muscina tri^imctata V. d. W. 

 This species, originally described from Mexico, was captured 

 by Mr. Busck, on Culebra Island, Porto Rico, in February, 

 1899, on excrement. 



Myosfila meditabunda Fabr. 

 This is a dull-colored fl}', about the size of the average com- 

 mon house fly, rather more sordid in its general appearance, but 

 very diflicult to distinguish from the house fly at a casual glance. 

 It iscommon to Europe and North America and is a widespread 



