HABITS OF THE ADULT FLY 
49 
article, that the fly in question was a house fly, but 
upon consulting an important paper by the same author 
(1906), entitled “Fungous Maladies of the Sugar 
Cane,” the same table is found printed on page 64 
and the fly in question is said to be a Sarcophagid, 
and therefore not Musca domestica. In his opening 
paragraph in the 1910 article, Doctor Cobb explains, 
“In some of these paragraphs, however, the statements 
are inferences fully justified by experiments with very 
similar species,” and this table is evidently one of these 
inferential statements. It is not safe to state that be¬ 
cause, as shown in the table, a well-fed Sarcophagid 
fly will defecate on the average once every four and 
one-half minutes, from half past nine until half past 
eleven, a true Musca will do the same. It is by no 
means impossible that it will do so, but unfortunately 
we have not the proof. Still with this explanation it 
will be interesting to state that in the interval between 
9:35 and 11:26 the fly observed by Doctor Cobb (it 
had been fed at 9: 23) made twenty-three fly-specks at 
intervals varying from one to fifteen minutes, an av¬ 
erage of about four and one-half minutes; and in ten 
of these twenty-three specks Doctor Cobb found spores. 
Herein lies one very great danger from flies. Certain 
authors believe that the danger from disease germs 
that pass through the fly’s body in this way is greater 
than from those that are supposed to be carried from 
foul substances on its feet. 
With the abundance of flies in the late summer, the 
number of fly-specks becomes almost unlimited. Doc- 
