. Animal parasites and human disease. Medical parasitology; Insects as carriers of disease. HABITS OF AEDES CALOPUS 447. will not live beyond 50 days, but the females frequently live under laboratory conditions for four months or more. Kind of food, dryness of climate and facilities for laying eggs are among the chief factors determining the length of life of these mosquitoes, and, strange as it appears at first, the length of life is shortest under the most favorable conditions, namely, plenty of blood for food, plenty of moisture, and suitable places for egg-laying. The flight of the yellow
. Animal parasites and human disease. Medical parasitology; Insects as carriers of disease. HABITS OF AEDES CALOPUS 447. will not live beyond 50 days, but the females frequently live under laboratory conditions for four months or more. Kind of food, dryness of climate and facilities for laying eggs are among the chief factors determining the length of life of these mosquitoes, and, strange as it appears at first, the length of life is shortest under the most favorable conditions, namely, plenty of blood for food, plenty of moisture, and suitable places for egg-laying. The flight of the yellow fever mosquito is strong but, like most other mosquitoes, it seldom flies long distances, usually not more than a few hundred feet. Vessels lying half a mile from shore rarely if ever are visited by these mosqui- toes unless the latter are carried from shore by lighters Or boats. Fig. 205. Pupa of yellow fever r\ ' i -i j ,• i i •, mosquito, Aedescalopus. X10. (After Owing to Its domestic habits Howard, Dyar and Knab.) and its ability to " stow away " the yellow fever mosquito has been, and annually is, widely distributed over the world. As pointed out by Howard, Dyar and Knab, its original home was very probably tropical America, since the evidence points to the origin of yellow fever in the West Indies and neighboring mainland, and it is inconceivable that the parasite of this disease would have developed in any other region than the original home of its obligatory host. The permanent home of this mosquito is now almost the entire warm portion of the world, wherever a temperature of 80° or more is maintained for any length of time, and where freezing does not occur. The once common occurrence and breeding of this mos- quito during summer months in cities of the Atlantic Coast of the United States and in other ports outside the frostless zones was due to its importation on ships from such infested cities as New Orleans, Havana and Rio de Janeiro. The cool nights
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918