Observations on certain physiological processes of the marmot. I.—The heart

Abstract

The temp. of marmots varies with that of the external air. The temp. of the heart of the hibernating marmot is the same as the rectal temperature. On raising the temp. of the environment to 14[degree] the rectal temp. rises, keeping about 3[degree] C. above that of the heart. Above this the heart has the higher temp. Experiments on the effect of temp. on the heart rate of the perfused and intact heart are described and discussed.