98 THE HISTOHY OF CEEATION. 



bladders arise from original semi-fluid globules of the primi- 

 tive slime, by the fact of their periphery becoming con- 

 densed. The simplest organism, as well as every animal and 

 every plant of higher kind, is nothing else than " an accu- 

 mulation (synthesis) of such infusorial bladders, which 

 by various combinations assume various forms, and thus 

 develop into higher organisms." Here again we need only 

 translate the expression little bladder, or infusorium, by the 

 word cell, and we arrive at the Cell theory, one of the 

 grandest biological theories of our century. Schleiden and 

 Schwann, about thirty years ago, were the first to furnish 

 experiential proof that all organisms are either simple cells, 

 or accumulations (syntheses) of such cells, and the more recent 

 protoplasm theory has shown that protoplasm (the original 

 slime) is the most essential (and sometimes the only) con- 

 stituent part of the genuine cell. The properties which Oken 

 ascribes to his Infusoria are exactly the properties of cells, 

 the properties of elementary beings, by whose accumulation, 

 combination, and varying development, the higher organisms 

 are formed. 



These two extremely fruitful thoughts of Oken, on account 

 of the absurd form in which he expressed them, were at 

 first little heeded, or entirely misunderstood, and it was re- 

 served for a much later era to establish them by actual 

 observation. The supposition that the individual species of 

 plants and animals originated from common prototypes by 

 a slow and gTadual development of the higher organisms out 

 of lower ones, was of course most closely connected with 

 these ideas. Man's descent from lower organisms was like- 

 wise asserted by Oken — " Man has been developed, not 

 created." Although many arbitrary perversities and ex- 



