208 THE DAWN OF LIFE. 



life wMcli are cliaracteristic of the animal. They can 

 seize, swallow, digest, and assimilate food; and, employ- 

 ing its albuminous parts in nourishing their tissues, 

 can burn away the rest in processes akin to our respi- 

 ration, or reject it from their system. Like us, they 

 can subsist only on food which the plant has previously 

 produced; for in this world, from the beginning of 

 time, the plant has been the only organism which could 

 use the solar light and heat as forces to enable it to 

 turn the dead elements of matter into living, growing 

 tissues, and into organic compounds capable of nourish- 

 ing the animal. Like us, the Protozoa expend the food 

 which they have assimilated in the production of 

 animal force, and in doing so cause it to be oxidized, 

 or burnt away, and resolved again into dead matter. 

 It is true that we have much more complicated appa- 

 ratus for performing these functions, but it does not 

 follow that this gives us much real superiority, except 

 relatively to the more difficult conditions of our exist- 

 ence. The gourmand who enjoys his dinner may have 

 no more pleasure in the act than the Amoeba which 

 swallows a Diatom ; and for all that the man knows of 

 the subsequent processes to which the food is sub- 

 jected, his interior might be a mass of jelly, with 

 extemporised vacuoles, like that of his humble fellow- 

 animal. The workman or the athlete has bones and 

 muscles of vastly complicated structure, but to him the 

 muscular act is as simple and unconscious a process as 

 the sending out of a pseudopod to a Protozoon. The 

 clay is after all the same, and there may be as much 



