48 VITAL POWER. 



tufts grow, the mass of formless, structureless bio- 

 plasm at the end of eacli moves onwards, the vessels 

 being developed in its rear. This formless living 

 matter moves forwards, burrowing, as it were, into 

 the nutrient pabulum, some of which it takes up as 

 it moves on. It is not pushed from behind, but it 

 moves forwards of its own accord. In a similar man- 

 ner the advancing fungus bores its way into the 

 material upon which it feeds, and the root filament 

 insinuates itself into interstices between the particles 

 of the soil, where it finds the pabulum for its nutri- 

 tion. 



13. Bioplasm of the hair. — In the hair the bioplasm 

 grows and multiplies at the base or bulb, pushing the 

 firm and already formed tissue before it. The bio- 

 plasm of the root of a plant increases at the extremity 

 of a filament Avhich it spins oS", as it wei'e, behind it; 

 in the case of the hair, on the other hand, the tissue 

 already formed is pushed on by the production of new 

 texture in its rear. The extremitv of the hair is its 

 oldest part, and nearest to its root is the tissue 

 which was most recently formed from pabulum 

 absorbed from the blood. 



14. Vital power. — But whether bioplasm moves on 

 in its entirety, or, advancing from a fixed point, forms 

 a filament, a tube, or other structure which accumu- 

 lates behind it, or remains stationary itself, Avhile the 

 products of formation are forced onwards in one 

 direction, or outwards in all, the nature of the force 

 exerted is the same, and due to the tnari'iellous power 

 tvhich one part of a living viass p)ossesses of moving in 

 advance of other portions of the same, as may be achially 

 seen to occur in the humhle amwha, in the mucus or in 

 the white blood-corpuscle from mrj,ns organism, as well 

 as in the pns-corpnscle formed in disease. 



15. Amoeba. — Among the simplest living things 

 known to us are the amcebse, which might be almost 

 described as animate masses of perfectly transparent 



