THE INFLUENCE OF PHYSICAL FACTORS 



95 



1. A toad which had been decerebrated a year before (fig. 28 x ). 



2. A frog (Rana temporarid] completely narcotized with ethyl- 

 urethane (fig. 28 + ). 



3. A frog of the same species immobilized with curari (fig. 28 Q). 



4. Frogs incompletely narcotized with urethane. 



5. Normal frogs. 



The temperature was found to have practically the same effect on 

 the metabolism in the three first-named cases, the differences being 

 within the experimental errors, and the curve obtained was the same 

 as that found by Ege and Krogh for a fish and by Krogh for a young 

 dog. Table XVI gives the results reduced to a common arbitrary 

 standard and fig. 28 the average curve and the experimental results 

 on which it is founded. Later Ellinger [1915] studied the resting 

 (standard) metabolism of gnats (Culex] at three temperatures from 3 

 to 20 and found that it conforms exactly to the above curve. 



TABLE XVI. 



On chrysalides of the meal-worm (Tenebrio molilor\ at the stage 

 when the respiratory exchange has reached a minimum (see below, 

 p. ill) and the muscles are to a great extent histolyzed, Krogh 

 [1914, I, 2] has made a number of experiments, the results of which 

 are extremely regular. The curve (fig. 29) representing the tempera- 

 ture influence upon metabolism is distinctly different from that 

 found for frogs, fishes, gnats, and the young dog, as seen when 

 the last column in Table XVI is compared with the average. 



It follows from all the above experiments that the velocity of the 

 catabolic reactions increases in all animals with rising temperatures 



