330 A. E. Verrill—The Bermuda Islands. 742 
can easily be carried to human food, to water, food receptacles, etc., 
or directly to the skin or to wounds. As they often fly long dis- 
tances in a few minutes, the danger is not merely local. A House- 
fly, carrying contagion on its feet, may fly in a few minutes from the 
worst tenement districts of any city to the largest hotels or most ele- 
gant houses of the wealthy, and entering their kitchens can deposit. 
the contagion on the costliest food or dishes, if exposed. 3 
Probably this method of spreading contagious diseases, usually 
ignored, explains in part at least the fact that health-resorts, far 
from cities, often soon become the reverse of healthy, owing to the 
diffusion of disease germs by flies, etc. 
The abundance of these flies in Bermuda, in summer, will be a 
source of danger in case of epidemics of any contagious diseases, or 
even with sporadic cases, for many of the dwelling houses do not 
have suitable sanitary arrangements for disposing of offal, or for pre- 
venting the access of flies. In winter and spring, when visitors 
mostly go there, these flies are fortunately not very numerous. Most 
of the larger hotels and boarding houses are now provided with 
good sanitary arrangements, but to exclude all flies is very difficult 
in summer, as in other warm countries.* 
Onionfly; Onion-maggot. (Phorbia ceparum=Anthomyia cepu- 
rum.) Figure 90. 
We were told that this species occurs, but obtained no specimens 
of it. The larve burrow in the bulbs of young onions. 
Anthomyia lepida was also recorded by Jones, 1876. 
Grape-fly ; Wine-fly; Vinegar-fly; Pomace-fly. (Drosophila 
ampelophila.) Figure 91. 
This small fruit-fly is very abundant wherever there is decaying 
fruit or fermenting fruit juices; it is often associated with other 
related species, not yet determined. It is also attracted to the dilute 
alcohol used in preserving specimens. The body is light, orange- 
brown ; abdomen with lighter yellowish bands. 
Cheese-maggot; Cheese-shipper; Dairyjfly. (Piophila casei.) 
This small, widely diffused fly is also found in Bermuda. Prob- 
ably it was introduced in cheese or bacon from Europe or America. 
It is about half as large as a House-fly, with a glossy black body. 
* A very liberal and frequent use of kerosene and of chloride of lime on all 
decaying or infected matter is very useful against flies and their larve. For 
further details, see L. O. Howard, Farmer’s Bulletin, No. 155, U.S. Dept. Agric., 
1902 ; and Year Book, U. S. Dept. Agriculture, for 1901, pp. 177-192. 
