88 Causes and Course of Organic Evolution 



complexity, but reaches its most striking climax in man, and 

 wliich is characterized throughout by definite reflex actions. 



When we study all of the life phenomena of these higher 

 Caryota up to man liimself the question may again be asked: 

 Can vre trace only bio tic and cognitic energies in their highest 

 degree of evolution and most perfect cooperation or action? 

 Or is there a higher type of energy associated with, and a causal 

 explanation for, evolution of the nerve cell, and which we in 

 general language have commonly called mind? We propose 

 in the remaining part of tliis chapter to indicate that such 

 exists. As being euphonious wdth the other energies, and 

 expressive of its function, we ^dll speak of it as the cogitic. 



Further, though such may seem highly illogical in treatment, 

 we propose first to study phases in man's history, for possible 

 verification of the position taken up. Having then obtained 

 some details as to the cooperation of biotic, cognitic, and cogitic 

 energy, as associated with and stimulating to formation of 

 the protoplasm, the chromatin or nucleo-protein, and the 

 Nissl substance or neuratin — as we will term it — of the nerve 

 cell, in the succeeding chapters we shall consider the two first 

 in detail, and shall leave to a later chapter like detailed con- 

 sideration of cogitic energy. 



Throughout such human study it T\'ill be necessary and 

 ai)propriate to view the organism alike in health and disease; 

 in developing, in growing, and in mature state; in the possession 

 of full life-^agor and in the successive stages up to death; in 

 normal activity and when affected by chemical agents; and 

 under average past environment, as well as amid changed 

 environal states. 



When we study the developing, gromng, and mature stages 

 of man, we learn that distinct and successive phases or accre- 

 tions of structure and activity are superadded on each other. 

 These are now minutely described in standard physiological 

 works, or in special treatises as those of Preyer (51), Ro- 

 manes (52: 213), Hobhouse (184^), Parmelee (53), and others. 



From the time that the human egg becomes a multicellular 

 structure, up to 1-4 days after birth, it performs functions 



