. Flies in relation to disease: bloodsucking flies. Flies; Flies as carriers of disease; Diptera. 40 PHLEBOTOMUS [CH. considerable force to a distance at least three times the length of the abdomen. The whole process occupied about two minutes, after which the insect appeared very fatigued and rested for at least three hours before continuing the egg-laying. The eggs are almost transparent when first laid, and are covered with a thin coating of sticky substance which causes them to adhere to any surface. They are very elongate in form, dark brown, shining, with longitudinal black wavy lines, w
. Flies in relation to disease: bloodsucking flies. Flies; Flies as carriers of disease; Diptera. 40 PHLEBOTOMUS [CH. considerable force to a distance at least three times the length of the abdomen. The whole process occupied about two minutes, after which the insect appeared very fatigued and rested for at least three hours before continuing the egg-laying. The eggs are almost transparent when first laid, and are covered with a thin coating of sticky substance which causes them to adhere to any surface. They are very elongate in form, dark brown, shining, with longitudinal black wavy lines, which are slightly raised and joined by very fine cross-lines. The length of the egg varies from O'l to 0'i5 mm. (Fig. 22.) The incubation period is usually from six to nine days, but the eggs are very susceptible to external conditions and will only hatch if kept in a moist atmosphere. 1. Fig- 22. Fig. 23. Fig. 22. Freshly extruded egg of P. papaiash. After Newstead Fig. 23. P. papatasii ; adult larva. After Newstead. The larva fives in damp earth and is very curious in form. It possesses a large weU-marked head with big jaws, the latter being provided with four distinct teeth. The body is covered with toothed spines that may serve as a protection against enemies, and the posterior end bears two pairs of black caudal bristles. The bristles of one pair are almost as long as the body, whilst those of the other pair are short, but increase in length in the later stages (Figs. 7 and 23). The length of the full-grown larva is about 2 • 3 mm. In India the larval stage usually lasts from about three weeks to even as long as two months, but its duration depends mainly on the temperature, being much prolonged in cold weather. The larva closely resembles a caterpillar in its movements ;. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishe, booksubjectdiptera
