90 THE GERM-PLASM THEORY 



time or other in the history of the earth, the con- 

 ditions necessary to the development of these 

 little invisible particles must have existed, and 

 that the whole subsequent development of the 

 organic world must have depended upon an aggre- 

 gation of these biophors into larger complexes, 

 and upon their differentiation within these com- 

 plexes. We shall' never be able, then, directly to 

 observe spontaneous generation, for the simple 

 reason that the smallest and lowest living particles, 

 which could arise through it, the Biophoridse, 

 are so extremely far below the limits of visibility 

 that there is no hope of our ever being able to 

 perceive them even if we should succeed in pro- 

 ducing them by spontaneous generation." ii., 369. 



In his amusing excursus on the " awful German 

 language." Mark Twain declares that the sentences 

 in that language are too much given to paren- 

 thesis ; there is the parenthesis, the re-parenth- 

 esis, the re-re-parenthesis and the all-embracing 

 King parenthesis. So in this theory we have the 

 assumption, the re-assumption, the re-re-assump- 

 tion and the all-embracing King-assumption. It 

 is assumed that the substance of the germ-cell is 

 not simple but complex ; it is assumed that this 

 complex body is made up of determinants for 

 different parts of the body ; it is ass^umed that 

 these again are built up of vital units each living 

 its own life, struggling with its neighbours, in- 

 fluenced by the nutritive stream by which it is 

 bathed ; and, finally, by an all-embracing King 

 assumption, these unseen, unprovable vital units 



