. Preventive medicine and hygiene. Fig. 25.—Larva of Stegomyia Syphon of Culex to the Right. MOSQUITOES 241 with a mouth and does not feed. It is an air-breather and spends mostof its time at the surface of the water. The pupal stage lasts at least3G hours, during which time metamorphosis occurs into the imago orperfect winged insect. Imago.—Under the most favorable conditions it is at least 9 daysfrom the time the Stegomyia lays its egg to the appearance of theimago. Under natural conditions the length of life of the adult femaleprobably varies greatly. Guiteras succeeded
. Preventive medicine and hygiene. Fig. 25.—Larva of Stegomyia Syphon of Culex to the Right. MOSQUITOES 241 with a mouth and does not feed. It is an air-breather and spends mostof its time at the surface of the water. The pupal stage lasts at least3G hours, during which time metamorphosis occurs into the imago orperfect winged insect. Imago.—Under the most favorable conditions it is at least 9 daysfrom the time the Stegomyia lays its egg to the appearance of theimago. Under natural conditions the length of life of the adult femaleprobably varies greatly. Guiteras succeeded in keeping a presumablyinfected one alive for 154 days during the fall and winter temperature. Fig. 26.—Pupa of Stegomyia Calopus. in Havana. Deprived of water, it does not usually survive longer than31/4 to 4 days, and only very exceptionally 5 days. This fact has abearing on the possibility of transporting the mosquito in band-boxes,trunks, and other containers. Aerial Conveyance.—It is notorious that yellow fever is usuallyconveyed but a short distance aerially—perhaps across the street, or,more often, to a neighboring house in the rear. This represents a dis-tance of some 75 yards, which is about as far as we may expect it tobe thus conveyed, from our knowledge of the habits and flight of theStegomyia mosquito. The longest distance recorded in recent years ofaerial conveyance is one of 225 meters (Melier) and one of 456 feet(Carter). These are entirely exceptional. My experience in the deten-tion of hundreds of susceptible immigrants in quarantine for days inHavana harbor showed that infected Stegomviae do not travel a short 242 IXSECT-BOEXE DISEASES distance across t
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Keywords: ., bookauthorwh, bookcentury1900, bookdecade1910, booksubjecthygiene
