INTR on UCTION. 3 



consciousness and intelligence is because in the struc- 

 ture of even the highest developed species we find no 

 specialised nerves or tracks along which sensations 

 can travel, or where they can be registered, as in 

 the ganglia and brains of the higher animals. 

 But it should be remembered that none of the 

 creatures included in the ancient and widely dis- 

 tributed sub -kingdom Protozoa possess a nervous 

 structure, whilst many in the next more highly 

 organised sub-kingdom Ccelentcrata have no trace, 

 and in the rest but a feeble development Yet we 

 do not deny these lowly organised animals a dim and 

 diffused consciousness, or even the possibility of their 

 structures being so modified that they can profit by 

 experience, and thus develop that accumulated ex- 

 perience of their kind we call instinct. 



The physical basis of life, Protoplasm, is the 

 same for plants as for animals. The first differ- 

 entiated or modified form of this we meet with is 

 the curious animalcule called Amoeba. As we watch 

 its movements we cannot refrain from ascribing to it 

 some dim consciousness of the life it leads. But 

 amoeboid structure is common even in the lowest 

 kinds of plants, and amoeboid movements can be seen 

 in some of their tissues. Witness also the habits 

 and intelligent movements of the zoospores of sea- 

 weeds and many other Algae, and the locomotion of 

 the antherozoa of Mosses, Ferns, etc. Not many years 

 ago these objects were classed as animalcules on this 



