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Howard (L. 0.). Remedies and Preventives against Mosquitos. — 

 U.S. Dept. Agric, Washington, D.C., Farmers' Bull. no. 444, 

 1917, 15 pp. 



Protection from the bites of mosquitos may be obtained by the use 

 of protective hquids, such as spirits of camphor, oil of pennyroyal, 

 oU of peppermint, lemon juice, vinegar, and oil of tar, of which a few 

 drops should be rubbed on the face and hands or sprinkled on the 

 pillow at night. The drawback to the use of these is, however, that 

 their effect does not last through the night. Oil of citronella retains 

 its effectiveness for several hours, while a mixture of oil of citronella 

 1 oz., spirits of camphor 1 oz., oil of cedar | oz., will usually keep the 

 common house mosquitos away if a few drops are placed on a towel 

 hung over the head of the bed, or rubbed on the face and hands. Even 

 this mixture loses its efficacy towards the end of a long night and 

 therefore offers no protection against the attacks of Stegomyia fasciata, 

 F. {Aedes calopus, Meig.), the yellow- fever mosquito, which begins to 

 bite at daylight. Another mixture, avoiding the use of oil of citronella 

 with its unpleasant odour, consists of castor oil 1 oz., alcohol 1 oz., 

 oil of lavender 1 oz. A mixture that successfully retards the evapora- 

 tion of the oil of citronella is made of oil of citronella 1 oz., and liquid 

 vaseline 4 oz. Oil of cassia, a 5 per cent, solution of potassivim 

 sulphate, and pure kerosene have all been recommended, the last 

 being extensively used in the PhiHppines. 



As a means of protection, the screening of houses, the use of netting 

 for beds, and the wearing of veils and gloves after nightfall are obvious 

 necessities in badly infested regions, while rain-water supply tanks and 

 barrels should also be screened, unless fish can be placed in them to 

 destroy the larvae. 



Smudges and fumigants consisting of substances that emit a dense 

 smoke on burning are commonly used in camps and houses. Of these 

 pyrethrum powders are very effective when fresh and pure, and are 

 most economically used by moistening and moulding them into small 

 cones, which, after drying, burn readily when lighted at the apex. A 

 more economical method is that of burning the powder on a metal 

 screen above the chimney of a kerosene lamp, though to clear houses 

 of mosquitos effectively, pyrethrum must be burned at the rate of 

 nearly 1 lb. powder to every 1,000 cu. ft. of space. 



Mimms culicide is a liquid that may be kept for some time in air- 

 tight jars, and is made of equal parts by weight of carbolic acid crystals 

 and gum camphor. The acid crystals are melted over a gentle heat 

 and poured slowly over the gum, forming a clear, rather volatile liquid, 

 with a pleasant odour. In fumigating, 3 oz. of this mixture should be 

 volatilised over a lamp of some kind for every 1,000 cu. ft. of space, 

 the rooms treated being made as nearly air-tight as possible. Fumiga- 

 tion against possible disease-bearing mosquitos is best effected by 

 burning lump sulphur in a small pot, at the rate of 2 lb. sulphur for 

 each 1,000 cu. ft. of space. Other recommended deterrents are the 

 burning of dried orange peel or powdered jimson weed {Datura 

 stramoninm) which burns more freely if mixed with nitre or saltpetre, 

 1 part to 3 of Datura. 



Descriptions of two apparatuses, one for catching and the other for 

 trapping mosquitos, are given, with a list of popular remedies for 

 mosquito bites. 



