THE BITING HOUSE FLY 
245 
eight days. In the puparium the insect remained from 
nine to thirteen days. The development of the species 
is therefore slower than that of the true house fly. It 
is Newstead’s opinion that the winter is passed chiefly 
in the pupal condition. Packard (1874) describes the 
pupa of this species. 
The extraordinary effects of numbers of the bites of 
this fly, indicated in the account of the epidemic of 
1908 in Argentina, cannot be exaggerated. Cattle and 
horses suffer severely from these bites when the in¬ 
sects are numerous. Mr. T. J. Bold, in the Entomolo¬ 
gists’ Monthly Magazine for 1865, p. 143, gives an 
account of the condition of these animals at Long 
Benton in September of that year. Fourteen cows 
were under treatment by a veterinary surgeon at one 
time. The animals were generally bitten on the out¬ 
side of the legs, on the shoulders, and, rarely, on the 
neck. In severe cases the joints were so much swollen 
that the animals could not bend their legs to lie down, 
and the swelling from the inflammation was so great 
that the outer skin cracked and the hair fell off. It 
is stated that the flies appeared to prefer the knees and 
upper portion of the foot of the cow, frequently crawl¬ 
ing from them to the hands of the veterinary, but their 
bites had no bad effect on him. It would seem from 
this as though animals are more susceptible than man. 
This biting fly has often been thought to be a dis¬ 
ease carrier and especially of blood parasites of do¬ 
mestic animals. The evidence for and against has been 
carefully considered by Austen (1909. p. 153), who 
