CoGiTic Evolution of IVIan 599 



and to produce therefrom a resultant stimulus, that by pro- 

 en vironal action started in the tissues a line of growth or motion 

 reaction, that was a satisfying resultant of all the incident 

 stimuli. The growth of Fungi and Algse; the movements of 

 roots, of stems, of leaves, of Paramoecia and other nucleated 

 Protozoa, of sponges, and the simpler coelenterates, would be 

 accounted for on such a basis, and can clearly be demonstrated 

 experimentally. 



One important result to be here noticed, in connection with 

 the studies of the present chapter, is that, within a single tissue, 

 even within a small area of it, such as the root-tip, the stem- 

 tip, the leaf-node of higher plants, or one end of protozoan 

 animals, when several stimuli have reached it from without 

 these are absorbed, compounded, and intrinsically affect the 

 living substance, so that one efferent stimulus, or possibly a 

 correlated set of stimuli, give rise to a motion that is a resultant, 

 in direction, in strength, and in duration, of all the stimuli 

 combined. We have seen that "sensitive plants," so-called, 

 exactly and quickly illustrate this, while protozoans and hy- 

 droids also agree. 



But with the appearance of ganglionic cells or nerve cells in 

 animals a new and more complicated situation presents itself, 

 that we have considered to be connected with evolving men- 

 tality, though at first the manifestations are of a very primi- 

 tive kind. 



The fundamental feature of mind activity or mentality is 

 that property which we call consciousness. As the word liter- 

 ally signifies, this is a knowing or comparing together of several 

 distinct resultant stimuli. This then leads to a combining of 

 two or more of these resultant impressions into a new compoimd 

 resultant, that becomes the line of action taken, while not in- 

 frequently one or more of the primary resultants is inhibited, 

 counteracted, or annulled in production of the new comi)ound 

 resultant. 



Though somewhat anticipatory, therefore, of the illustra- 

 tive cases to be cited in this chapter, we may shortly set forth 

 the relation of biotic, cognitic, and cogitic acts as follows: 



