132 INSECTS AFFECTING DOMESTIC ANIMALS. 
in which they have developed, and bury themselves in the ground to 
transform. 
The puparia are brown in color, cylindrical, rounded at the ends, and 
about two-fifths of an inch in length. (See fig. 69.) 
The length of time passed in the pupa stage appears to vary, but 
observers agree on from nine to twelve days as the usual time; Francis 
Says nine for the shortest and fourteen for the longest period observed 
by him. From this history it is evident that there may be a succession 
of many generations during a season, which for different individuals so 
Fig. 66.—Egg of C. 
macellaria—great- 
ly enlarged (after 
Francis). 
Fig. 68.—Larvaof OC. macellaria—enlarged (after 
Francis). 
Fic. 67.—Egg mass of 0. macellaria (after Francis). 
overlap and combine that there are hosts of the insects in all stages, 
from their appearance in the early part of the season till checked by 
return of cold weather. As Francis says: 
While the larve are thus developing, the flies are constantly laying fresh eggs in 
the wounds, so that the young worms take the places of the matured ones, and thus 
keep up a constant and progressive loss of tissue. 
REMEDIES. 
It is evident from the above accounts that the fatal cases in man are 
due to the deposition of eggs, mainly in the nostrils, sometimes in the 
Fie. 69.—Puparium of C. macellaria—en- Fia. 70.—Puparium of C. macellaria, showing 
larged (after Francis). broken end where fly has emerged—enlarged 
(after Francis). 
mouth, and that such deposition is most liable to occur to persons sleep- 
ing in the open air or to those suffering from catarrh. The evident 
precaution is to avoid these sources of danger by the use of mosquito 
netting or wire gauze for sleeping rooms and of a protection for the 
nostrils when exposed in places where the flies are common. 
If once infested, medical attention should be sought at the earliest 
