ENTOMOLOGY

•CONTROL OF THE HOUSE FLY AND RELATED FLIES 165Bacot recommends a kerosene emulsion of 3 parts soft soap completelymelted by heat in 15 parts of water and the addition up to 100parts of kerosene or other light burning oil, and churning up to anemulsion. This may be kept indefinitely and diluted with water to about1 part emulsion to 10 parts water content.Protection of Animals.-Animals are seriously bothered by the pesteringof flies. Any kind of netting that the animal can shake to disturb theflies is of some value. The question of repellents is one upon which manyinvestigators have labored. Graybill, 1914,8 summarizes the results ofthese investigations. Those formulae most in use all contain crudepetroleum oil and usually soap.A good stock emulsion recommended by Graybill is made of:Hard soap, 1 pound,Soft water, 1 gallon,Beaumont crude petroleum, 4 gallons,Dilute to 1 part emulsion to 3 parts water.Bishopp's fly repellent consists of:Fish oil, 1 gallon,Oil of tar, ~ ounces,Oil of pennyroyal, ~ ounces,Kerosene, 1/2 pint.For dairy cattle, Jensen makes a stock solution of crude ~ etroleumwith the addition of 4 ounces powdered napthalin, and applies with abrush once or twice a week.Jensen has also given three formulm of repellents for ,J?l1"otectingwounds from flies.Formula No.1:Oil of tar, 8 ounces,Cotton seed oil to make 3~ ounces.Formula No. ~:Powdered napthalin, ~ ounces,Hydrous wool fat, 14 ounces,Mix into an ointment.Formula No.3:Coal tar, 1~ ounces,Carbon disulphid, 4 ounces,Mix; keep in a well stoppered bottle and apply with a brush.It is of the utmost importance that flies be kept at a minimum in armycamps. We can do no better than cite a few authorities of the variousarmies in support of this. Ainsworth considers the presence of the housefly the greatest danger signal to an Ilrmy in the field. Savas has cal,led• Repellents for Protecting Animals from the Attacks of Flies, U. S. Dept.Agr. Bul. lSI.