8 THE STABLE FLY. 
were present to furnish their quota of the pest. In fact, the flies 
were so numerous around these stacks that many men in plowing 
their fields avoided, so far as possible, the portions adjacent to them. 
Although the stacks dried out rapidly on the surface, the straw 
beneath continued moist for several months, and flies continued to 
emerge from these stacks where the straw was not destroyed or where 
breeding was not otherwise prevented. 
Dr. L. O. Howard published a note a few years ago calling atten- 
tion to a report by Prof. Iches on an invasion by this fly of a large 
estate in the Province of Santa Fe, Argentina. This occurrence 
appears to have been very similar to the recent outbreak in Texas. 
The flies were found by Prof. Iches to be breeding in wheat and 
flax straw after threshing. 
HOSTS. 
Practically all warm-blooded animals are attacked by this insect. 
Some of our domestic species, however, are much freer from injury 
than are others, owing to protection afforded the host by its hair or 
by some habit. Mules in general seem to be more annoyed by the 
flies than any of the other domestic live stock. Horses and cattle 
are, however, heavily attacked and often suffer severe injury. Those 
animals which are not easily disturbed and irritated act as hosts for a 
greater number of flies, but the result is probably not so serious as 
with more nervous individuals, which are consequently more easily 
worried. Sheep and goats are attacked on parts of the body not 
protected by wool, particularly the legs. Hogs are often attacked, 
especially when they are free in pastures. The flies are not attracted 
to the hog pens as are house flies, and where the animals have access 
to mud they are seldom bitten to any great extent except when flies 
are extremely abundant. Dogs and cats have also been seen with 
flies feeding upon them. Dogs with thin hair are exceedingly sus- 
ceptible to injury and are greatly worried by the attacks. In some 
cases the flies become sufficiently numerous, especially on the ears, 
where they are inclined to feed most commonly, to cause the blood 
to trickle from the bites. In a few instances chickens have been seen 
with flies feeding upon their combs; however, healthy poultry are so 
active, as well as so largely protected, that they are seldom annoyed. 
Man is also frequently attacked by this pest, although the attack is 
usually quickly discovered on account of the pain caused by the 
insertion of the beak. During severe outbreaks men engaged in field 
work are often greatly annoyed by the flies, which not only attack 
exposed portions of the body but are able to bite through shirts or 
other comparatively thin garments as well. The flies also frequently 
attack the ankles of people, especially when low shoes are worn. 
540 
