The recovery heat production in non-myelinated garfish olfactory nerve fibres.

1. The recovery heat production of the non-myelinated fibres of garfish olfactory nerve has been measured. 2. At about 20 degrees C the total recovery heat was 381 +/- 26 microcal g-1 impulse-1 at a stimulation frequency of 2 sec-1. 3. The time constant of decay of the recovery heat production after a brief period of stimulation was 78.7 +/- 3.1 sec at about 20 degrees C. 4. Changing the temperature (by +/- 5 degress C) had little effect on the total recovery heat produced. 5. However, lowering the temperature reduced both the rate of rise, and the maximum rate of recovery heat production whereas the time constant of decay was increased. Raising the temperature produced corresponding changes in the opposite direction. 6. the recovery heat production measured in the present experiments is consistent with the previously measured oxygen consumption in the same preparation.