286 NATURAL SELECTION 



tionists will probably be discovered, but I shall not venture 

 to speculate as to the probable tenor of these in this 

 place. 



I am of opinion that if the resemblance in structure 

 between different living forms had been far greater than it is, 

 the differences would nevertheless have struck any unbiassed 

 observer as so remarkable and so numerous, that he would 

 have objected to ground any general inference whatever 

 on the fact of likeness alone. What can be more like 

 than different forms of bioplasm ? But it would be un- 

 justifiable on that account to infer that all forms of bioplasm 

 sprang from one or a few primitive stocks. I have, however, 

 no doubt that some of my readers will insist that this cir- 

 cumstance greatly strengthens the argument already deemed 

 more than sufficient to prove the truth of the evolutional 

 hypothesis. To me, however, it appears that the like- 

 ness between different forms of bioplasm tells against that 

 favoured doctrine. The likeness, though far greater than 

 that existing between any well recognized but distinct 

 species of animals is but a likeness in certain particulars. 

 Anyone who affirmed from this likeness that different forms 

 of living matter were identical, would affirm that which can be 

 shown to be erroneous. Two forms of living matter may be 

 indistinguishable by observation or experiment, and yet they 

 may be as widely removed from one another as are the 

 poles. The remarkable differences, however, are not of 

 a kind to be expressed in any terms known to physics and 

 chemistry. They must be referred to powers that have been 

 handed down by preceding bioplasm. Such differences are of 

 the vital kind, and although not recognizable by the balance 

 or the microscope their existence must be admitted unless all 



