I9I4.] CRILE— THE KINETIC SYSTEM. 265 



alterations in the efficiency of the cerebral link may yield neuras- 

 thenia, mania, dementia ; of the thyroid link, — Graves' disease, 

 myxedema; of the suprarenal link, — Addison's disease, cardiovas- 

 cular disease. 



This introduction may serve to give the line of our argument. 

 We shall now consider briefly certain salient facts which relate to the 

 conversion of latent energy into kinetic energy as an adaptive reac- 

 tion. The amount of experimental data is so large that they will 

 later be published in a monograph. 



The amount of latent energy which may be converted into kinetic 

 energy for adaptive ends varies in different species, in individuals of 

 the same species, in the same individual in different seasons ; in the 

 life cycle of growth, reproduction and decay; in the waking and 

 sleeping hours ; in disease and in activity. We shall here consider 

 briefly the reasons for some of those variations and the mechanism 

 which makes them possible. 



Biologic Consideration of the Adaptive Variation in Amounts 

 OF Energy Stored in Various Animals. 

 Energy is appropriated from the physical forces of nature that 

 constitute the environment. This energy is stored in the body in 

 quantities in excess of the needs of the moment. In some animals 

 this excess storage is greater than in other animals. Those animals 

 whose self-preservation is dependent on purely mechanical or chem- 

 ical means of defense, such animals as crustaceans, porcupines, skunks 

 or cobras, have a relatively small amount of convertible (adaptive) 

 energy stored in their bodies. On the contrary, the more an animal 

 is dependent on its muscular activity for self-preservation the more 

 surplus available (adaptive) energy there is stored in its body. It 

 may be true that all animals have approximately an equal amount 

 per kilo of chemical energy — but certainly they have not an equal 

 amount stored in a form which is available for immediate conver- 

 sion for adaptive ends. 



Adaptive Variation in the Rate of Energy Discharge. 

 What chance for survival would a skunk have without odor ; a 

 cobra without venom ; a turtle without carapace ; or a porcupine 



