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AURORA AUSTRALIS. surviving all kinds of climatic rigours, heat, cold, drought, etc..

Larger animals may protect themselves from heat and cold in various ways, or they may migrate to avoid them. Emperor Penguins and other animals which winter in polar regions, keep up their heat by means of thick layers of fat and warm coats of fur or feathers. No such protection can serve our microscopic animals. A thin-skinned creature, measuring when contracted no more than one hundredth part of an inch in diameter, can hardly have a coating which will keep out cold and heat, and we can only suppose that they are able to live although they do become very hot and very cold when subjected to these conditions.

A heavy swell is rolling in from the Atlantic and breaking on the rocks of a rugged little western seaport. On the cement wall of the pier the waves are rushing and climbing high up, till they are thrown