MATTDSLEY ON HEREDITARY DESCENT. 47 



11. As the co-ordinating power which is the cause 

 of form in organisms cannot be found in matter, it 

 must be looked for outside of matter. Like any 

 other cause, its nature must be judged of from its 

 effects. 



Any man who has stood face to face with the re- 

 sults of microscopical research in the last twenty 

 years will, I think, be very slow to adopt any other 

 than Aristotle's definition of life. Perfectly parallel 

 with that definition is the one given here. 



12. Life is the immaterial co-ordinating power be- 

 hind the movements of germinal matter. 



That definition having been defended by me at 

 great length previously, I shall now use our former 

 conclusions. From the point of view reached in thir- 

 teen lectures on Biology (see vol. i. of the Boston 

 Monday Lectures), I must begin — and I can only 

 begin to-day — a reply to Maudsley. 



1. Germinal matter, or bioplasm, increases in quan- 

 tity as living tissues grow. Once every living thing 

 was but a single naked mass of bioplasm. 



2. With the increase of quantity there is an in- 

 crease of the force in the germinal matter. 



Your naked, throbbing mass of bioplasm takes on 

 a wall, and divides and subdivides, and weaves the 

 walls of its cells into tendon and nerve and muscle, 

 and coils these around each other, according to a 

 predetermined plan. One-fifth of the bulk of the 

 mature organism is made up of germinal matter. 

 One bioplast? develops into many. 



3. Tliis increase is derived from the assimilation 

 of inorganic matter. 



