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2. Hibernation of the Larva. —The larvae of 
certain Anophelines , e.g., A. bifur catus, appear able to 
resist low temperatures, and are found even when 
parts of the water are frozen over. Under these 
circumstances they grow extremely slowly, if at all. 
So also in the tropics, different species tide over 
the £ cold weather 5 in different ways. Thus James 
found that M. culicifacies hibernated by means of 
larvae only, little or no growth occurring in these 
(t. = 55°F. about): whereas Ce. pulcherrima and N. 
fuliginosus laid eggs which developed into pupae and 
imagines. 
3. Hibernation of Eggs. —There is a certain 
amount of evidence to shew that eggs can survive 
for some months in moist earth, exposed to frost, etc. 
For young larvae have been found in fresh pools in the 
winter, under conditions that made it unlikely that 
the eggs had been deposited there on the appearance of 
water. The resistance of eggs to drying under a 
tropical sun is, however, practically nil. 
Mode of Dispersal of Anophelinae 
There is no evidence existing at present to show 
that mosquitoes habitually disperse any considerable 
distance from their breeding-grounds. In fact, the 
evidence is completely against such a dispersal, and, 
broadly speaking, the Anophelinae remain where they 
were developed, and in the native huts where they 
find abundant food. 
That various accidental modes of distribution 
occur is equally certain, e.g. :— 
1. On trains, boats, and even ocean-going 
steamers, they may be carried long distances, e.g ., from 
West Africa and South America to England, but it 
