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AURORA AUSTRALIS. resume their interrupted life.

It is a curious result of this faculty of resisting dessication that animals which would terminate their natural life, probably in a few hours, at the utmost in a few weeks or months, may live over a long period of years.

Whether an individual, after hibernating in this manner for many years, could again enter on a long hibernation, is not known, but groups of individuals have been revived again and again after shorter intervals, though in diminishing numbers, some dropping out after each resuscitation.

The capacity to resist heat is intimately related to that of withstanding drought. In a state of nature, some Bdelloids when dessicated, must also suffer very severe scorching from the tropical sun; yet mosses from tropical regions are found to be as productive of Bdelloid Rotifers as any others, and they readily revive when conveyed to temperate regions and steeped in cold water.