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LIFE UNDER DIFFICULTIES. Artificially some of these Bdelloids have been raised to very high temperatures. The actual figures given by Davis and others are not here available, but the temperature to which they were raised was certainly higher than anything to which they would be subjected under natural conditions anywhere on the surface of the earth, and many were revived after this treatment.

The Rotifers which are able to endure cold should interest us especially in our present circumstances, as they are at the moment under observation in the lakes around us at Cape Royds, and we have some personal experience of the cold which they have to undergo.

Bdelloid Rotifers abound in the lakes of Cape Royds, and there are several species. The conditions to which they are submitted are extremely severe. They are frozen into the ice very early in the autumn, and must remain frozen solid for at least the greater part of the year. With the ice of the smaller lakes and the margins of the larger lakes they must take the