PSYCHIC ADAPTATION 107 







of repose ; on the right the cell similar a is, on the 

 contrary, in an artificial state of activity. 



" A single experiment may very well be deemed 

 insufficient. It was therefore repeated by again 

 placing the lizards in the stove for from one to 

 three days, but this time at 25 Cent. The result 

 was the same. 



" Being now certain of the phenomenon, inquiry 

 was made as to the least duration of time in the 

 stove necessary for the winter neurofibriles to 

 transform themselves into active filaments. This 

 duration was found to be an hour at most. 



" Other hibernating animals, e.g. snakes, were 

 subjected to the same experiments, and the 

 neurofibrile frame of their cells underwent similar 

 transformation. 



" When the spring at length arrived, the lizards 

 revived spontaneously and were killed. There 

 was only in the cells of their marrow the tangled 

 reticulum of innumerable fibre filaments. 



"The demonstration was therefore complete." 



When one sees clearly how a brain that is, the 

 substance whose active power depends solely and 

 exclusively on the whole psychic activity can be 

 changed in the quantity and quality of its delicate 

 elements, and that its state of integrity depends 

 in the last resort on a phenomenon of nutrition, 

 there is no further need to explain these changes 



