554 THE ECONOMIC STATUS OF INSECTS AS A CLASS. 



AS INJURIOUS TO LIVE STOCK AND OTHER USEFUL ANIMALS. 



Every species of animal which has become domesticated and is of 

 value to man possesses its insect parasites and enemies. These in 

 many cases are the same species which affect man and which we will 

 mention in the next section; others are specific to the animals or 

 groups of animals which they affect. Horses, cattle, sheep, all possess 

 insect enemies which are not only very deleterious to their health, 

 but frequently cause their death in numbers. 



The disgusting bot fly of the horse, whose maggots live in incredi- 

 ble numbers in the stomach and intestines of this noble friend of the 

 human race ; the bot fly of the ox, which causes innumerable sores on 

 the backs of cattle and by its perforations ruins their hides for com- 

 mercial use; the bot fly of the sheep, which inhabits the nasal and 

 orbital sinuses of the sheep and produces insanity and death, will 

 instantly be recalled by those who are familiar with stock raising, 

 while hundreds of other species, some in no less degree, as the horn fly, 

 the numerous gadflies, including the tsetse fly of Africa, the screw- 

 worm fly of our Southwestern country, unite to make the lives of 

 domestic animals a burden to themselves and a trial aud a loss to their 

 owners. 



An interesting attempt was made some years ago by a prominent 

 Western agricultural newspaper, The Farmers' .Review, to estimate 

 approximately the pecuniary loss from the attacks of a single one of 

 these insects — the ox bot fly, or ox warble — on the cattle received at 

 the Union Stock Yards of Chicago. It was estimated that 50 per cent 

 of the cattle received each year are affected. The number of cattle 

 received at the yards during 6 months of the year 1889 was 1,335,026; 

 the average value of the hide was $3.90; the usual deduction for hides 

 damaged by the ox warble was one-third. Estimating at less than one- 

 third, say $1, the actual loss during six months on hides alone was 

 $667,513. When to this was added the loss for depreciation in value 

 and lessened quantity of beef, the loss for each infested animal was 

 put at $5, a very low estimate, indicating the total loss from the ani- 

 mals in the Union Stock Yards of Chicago for a period of six months 

 of $3,336,565. 



AS ANNOYING MAN. 



There are very few regions of the habitable globe where man is not 

 personally subject to more or less annoyance by insects. In this part 

 of the world we naturally think at once of mosquitoes, house flies, fleas, 

 and of a certain other species which it will not be necessary to name. 



A susceptible individual some years ago wrote to the Department of 

 Agriculture and said that he had come over from the old country and 

 settled in New Jersey, but that the mosquitoes bothered him so greatly 



