10 CELL INTELLIGENCE THE CAUSE OF EVOLUTION 



see. No one seems to know what is understood by this 

 word. Mr. Binet seems to be also of the same opinion 

 and states : "The term irritability, which though long in 

 use has not in our opinion been happily chosen, since it 

 is in the highest degree ambiguous and not suggestive of 

 an exact signification." 



The little fresh water cell we call amoeba, who leads a 

 separate independent life, is so very similar to those that 

 build animals and man that the microscope can discover 

 no difference. Mr. Binet described his actions as fol- 

 lows : "The following is what occurs when the amoeba 

 in its rampant course happens to meet a foreign body. 

 In the first place, if the foreign particle is not a nutritive 

 substance, if it be gravel for instance, the amoeba does 

 not ingest it ; it thrusts it back with its pseudopodia. 

 This little performance is very significant ; for it proves, 

 as we have already said, that this microscopic cellule in 

 some manner or other knows how to choose and distin- 

 guish alimentary substances from inert particles of sand. 

 If the foreign substance can serve as nutriment, the 

 amoeba engulfs it by a very simple process." 



You will see from this that his actions show discre- 

 tion. In hunting for food he must exercise his judgment 

 at all times as to where he is going and as to whether 

 this or that is suitable for food. Such action of choosing 

 must be based on former experience, which involves 

 memory. Again here is what Mr. Binet has to say about 

 the actions of cells, showing how they act when living 

 as separate beings and not in those vast co-operative 

 colonies we call plants and animals : "The Infusoria 

 when in a medium abounding in food are almost entirely 

 sedentary in their habits, only making slight changes of 

 position. But if they are placed in a medium affording 

 but little nutritive material, they become as migratory 



