152 WHAT MAY BE LEARNED FROM EOZOON 



siderations suggested by the probable origin of animal life in 

 the seas of the Laurentian period. 



Looking down from the elevation of our physiological and 

 mental superiority, it is difficult to realize the exact conditions 

 in which life exists in creatures so simple as the Protozoa. 

 There may perhaps be higher intelligences, that find it equally 

 difficult to realize how life and reason can manifest themselves 

 in such poor houses of clay as those we inhabit. But placing 

 ourselves near to these creatures, and entering, as it were, into 

 sympathy with them, we can understand something of their 

 powers and feelings. In the first place it is plain that they 

 can vigorously, if roughly, exercise those mechanical, chemical, 

 and vegetative powers of life which are characteristic of the 

 animal. They can seize, swallow, digest, and assimilate food ; 

 and, employing 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 sub- 

 sist 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 nourishing the animal. Like us, the Protozoa ex- 

 pend 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 apparatus for performing 

 these functions, but it does not follow that these give us much 

 real superiority, except relatively to the more difficult condi- 

 tions of our existence. The gourmand who enjoys his dinner 

 may have no more pleasure in the act than the Amceba which 

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

 subsequent processes to which the food is subjected, his in- 

 terior might be a mass of jelly, with extemporised vacuoles, 



