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142 hatched out to deposit her own eggs, and that she rarely strays from the vicinity more than a few yards, quite exceptionally beyond half a mile. Occasionally she may be blown for some distance by gentle winds; and it is believed that in certain circumstances, probably connected with food supply and over-stocking, she will travel singly or in vast swarms for long distances. Such migrations, however, are quite unusual. Of course, mosquitoes may be, and often are, transported great distances in ships, railway carriages, and similar vehicles, and in this way man aids in their diffusion; but for the most part the mosquito is a feeble and timid flyer, disliking to

Fig. 29. Pupa of Anopheles maculipennis. Pupa of Culex fatigans.

leave her accustomed haunt, and seldom rising high above the ground. So soon as even a moderate breeze springs up she seeks shelter in bush, or house, or cranny. Some species are domestic; others live exclusively in jungle or forest; some, after passing the day in the open, visit human habitations, or the haunts of birds and beasts, during the night. The great majority of species are nocturnal in habit, although many of these can be coaxed into activity by the reproduction of night-like conditions of shade and atmospheric stillness.

The accompanying figures (Figs. 23-39) give a good idea of the leading features of the anatomy of the mosquito and of the names applied to the various