THE PROPERTIES OF PROTOPLASM 13 



the two oppositely but simultaneously proceeding 

 phases of metabolism, anabolism and katabolism. 

 So, too, the precise state of the vital manifestations 

 at any given moment is the result of the degree of 

 intensity of affectability and of functional inertia 

 possessed at that moment by the living matter in 

 question. For each property must, or at any rate 

 may, vary from moment to moment : each may 

 vary absolutely and relatively to the other, and in 

 some way the intensity of the possession of these 

 two simultaneously varying factors at any given 

 moment must be related to the particular inter- 

 relations of the two simultaneously proceeding 

 metabolic phases. This relation between the pro- 

 perties and stimulation may be illustrated by 

 definite example. Wedensky * has shown that 

 glands which would not secrete when stimulated by 

 very strong electrical stimuli, would do so if much 

 weaker stimuli or stimuli at a slower rhythm were 

 resorted to. There was insusceptibility towards 

 stimuli above a certain maximum of strength and 

 above a certain optimum of rate. (Wedensky 

 remarks on the secreto-motor latent period in all 

 these cases.) Similarly, von Kries and Sewall f 

 have found that in cooled nerve, electric oscillations 

 of 100 per second failed to produce tetanus, the 

 initial twitch alone being produced. I have noticed 

 the same thing at room temperature in the muscles 

 of the abdominal somite of the lobster. 



* Wedensky, Compt Rend., vol. cxv. 1892, p. 1103. 

 | Sewall, Journ. Phys., vol. ix. 1898, p. 92, 



