INSECTS AFFECTING HEALTH OF MAN OR ANIMALS. | 3 
feeding ground in search of a favorable place in which to pass the 
pupal or resting stage. They will often congregate at the edges of 
manure piles near or in the ground, or they may crawl away from the 
pile and pupate in the ground or in loose material under the edges of 
stones, boards, etc. Then the maggot contracts and its old skin 
forms a barrel-shaped case with rounded ends within which the adult 
fly is gradually formed. This pupal or resting stage is shown in 
figure 3. The duration of this stage is from 3 to 10 days and the total 
time from laying of eggs to the emergence of the adult fly is from 
8 to 15 days. 
Fic. 1.—Eggs of the house fly, About naturalsize. (Newstead.) 
PRACTICAL CONTROL OF THE HOUSE FLY AND INSECTS BREEDING IN MANURE AND 
LATRINES. 
The disposal and treatment of manure.—In the arid region along the 
Mexican border perhaps the best way of disposing of manure is the 
following method adopted by Lieut. H. C. Michie:! 
Spread the manure evenly not to exceed 4 inches in depth in such 
a manner that the wagons will not have to run over it after it has 
once been spread. Burn when dry enough (in about two days). Use 
space again. It is important to have the surface uniformly covered, 
as it will be easier to burn. 
A shght modification of this method? has been used in certain 
camps. ‘This consists in dumping the manure from the tail of wagons 
1 The Military Surgeon, v. 35, p. 132-148. 1914. 
2 See Miller, Military Surgeon, v.33. December, 1913. 
