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AURORA AUSTRALIS. lowest temperatures that occur in the district. We know by observation that they survive after experiencing a temperature of -30° Fahr.. They were found living in the Blue Lake under 15 feet of ice, there being some reason to believe that at this depth melting may only occur at intervals of years.

It has been generally assumed that animal life ceases at the temperature at which water freezes, and this is in the main true of animals which swim in water, but whether the death is due to cold or to mechanical causes is not known.

Those who have worked at the microscopic life of the Arctic Region know that it must survive extreme cold. somehow. The Arctic Region has a, genial summer climate of some months duration, with abundant water and a vegetation of higher plants. The winter might be passed by resting eggs, and a new generation produced each summer. Professor Richters revived Water Bears from Spitsbergen some years after they were collected, but it could not be known whether the adult animals would have survived the winter of their native land.

At Cape Royds there is no doubt that the adult animals survive through the winter. Some of the species lay eggs, but the eggs are not plentiful. One