Instinct Inherent in Protoplasm 23 



of chemical energy. When an Amoeba has 

 grown to a definite size its nucleus and body- 

 substance separate into two parts which move 

 away from one another, and two young Amoebae 

 are formed exactly resembling their parent. 



Amoebae from time to time, in response to 

 certain stimuli, extend outwards retractile pro- 

 cesses from their body substance known techni- 

 cally as pseudopodia. By aid of these feelers 

 an Amoeba is able to move about over the mud 

 forming the bottom of the pond it inhabits. 

 When an Amoeba comes in contact with solid 

 particles, Dr. Dendy 1 writes, we notice that it 

 has the power of distinguishing one particle 

 from another, and that one which is good for 

 food adheres to a pseudopodium and is carried 

 into the body of the animal, where it is digested. 



Professor G. C. Bourne, when describing 

 Protozoa, or single-cell organisms, remarks that 

 they must exercise some sort of selection in in- 

 gesting solid matter; for if they did not they 

 would take in every particle of convenient size 

 that they meet, and they do not. He further 



1 Outlines of Evolutionary Biology, by A. Dendy, D.Sc., F.R.S., 

 p. 16. 



