THERMOTAXIS igi 



and thus compensation is established. A cold bath lowers 

 the temperature because heat loss is increased more than 

 heat production. There is increased radiation because of 

 the relatively increased difference in the temperature of the 

 body and of the surrounding medium. On the other hand, 

 the cold contracts the capillaries, diminishing the amount 

 of blood exposed to the cooling influence of the water and 

 decreasing the amount of sweat ; but these influences tend- 

 ing to inhibit heat loss are not equal to those augmenting 

 it. However, in health, thermotaxis prevents the disturb- 

 ance of the balance between thermogenesis and thermolysis 

 to any great extent, and the temperature cannot be lowered 

 very much. These are only examples of the reciprocal re T 

 lations maintained between the production and dissipation 

 of heat, a disturbance of which relations is prevented under 

 normal conditions by thermotaxis. Any change in one pro- 

 cess is followed at once by a compensatory change in the 

 other. 



