. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. BREEDING OF AEDES CALOPUS 445 laid from four to seven days after a blood meal. The nearest allies of this species are tree-hole breeders, but the yellow fever mosquito has become domesticated to such an extent as to much prefer a rain barrel or water-filled tin can in a garbage heap, or, even better, a water-pitcher or flower-vase indoors. Churches in Central America are usually well supplied with yellow fever mosquitoes which breed in the holy-water Fig. 203. A yellow fever center in Panama in
. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. BREEDING OF AEDES CALOPUS 445 laid from four to seven days after a blood meal. The nearest allies of this species are tree-hole breeders, but the yellow fever mosquito has become domesticated to such an extent as to much prefer a rain barrel or water-filled tin can in a garbage heap, or, even better, a water-pitcher or flower-vase indoors. Churches in Central America are usually well supplied with yellow fever mosquitoes which breed in the holy-water Fig. 203. A yellow fever center in Panama in the pre-American days. (Drawn from photo from Thompson.) The eggs (Fig. 193C), up to 150 in number, are laid in several lots at intervals of a few days, either on the surface of the water, or, as is more common, on the edges of the container, or on a partially submerged object, wherever a moist surface is presented and where a slight elevation of the water will submerge them. The female mosquitoes die a short time after the last batch of eggs is laid. According to Bacot's experiments the promptness of hatching depends on temperature and on whether the eggs have been kept under moist or dry conditions. The eggs of this species retain their vitality for several months when kept absolutely dry, but they hatch more readily and with less mortality if kept moist. When the eggs are laid directly on the surface of water they ma- ture less rapidly than when laid above the surface, probably on account of the cooling effect of the water. Eggs laid on the surface hatch in a minimum of two days, while those above it, if later submerged, may hatch in less than 12 hours. Accordmg to recent work by Atkin and Bacot, eggs will not hatch in sterile water, but will hatch within a few hours after the introduction of living bacteria. The larvae (Fig. 204) thrive in either clean or foul. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918
