ISO THE MECHANISM OF LIFE 



of such marvellous results should have hitherto been almost 



"S* 



A second analogy between vital and osmotic growths 

 is to be found in their structure, both being formed by groups 

 of cells or vesicles separated by osmotic membranes. An 

 osmotic stem, formed by a row of cellular cavities separated 

 bv osmotic membranes, has a great structural resemblance 

 to the knotted stems of bamboos, reeds, and the like. The 

 foliaceous expansions of osmotic growths are formed by colonies 

 of cells or vesicles disposed in regular lines, which may 

 present various patterns of innervation, parallel, palmate. 

 or pennate. Many of the lamellar osmotic growths are 

 striped in parallel lines alternately opaque and transparent. 

 The terminal organs have also their enveloping membranes, 

 their pulp and nucleus, just like vegetable forms. 



The analogies of function are no less remarkable than 

 those of form and structure. Nutrition is perhaps the most 

 elementary and essential vital phenomenon, since without 

 nutrition life cannot exist. Nutrition consists in the absorp- 

 tion of alimentary substances from the surrounding medium, 

 the chemical transformation of such substances, their fixation 

 by intussusception in ever) part of the organism, and the 

 ejection of the products of combustion into the surrounding 

 medium. Osmotic growths absorb material from the medium 

 in which they grow, submit it to chemical metamorphosis, 

 and eject the waste products of the reaction into the sur- 

 rounding medium. An osmotic growth moreover exercises 

 choice in the selection of the substances which are ottered for 

 its consumption, absorbing some greedily and entirely rejecting 

 others. Thus osmotic growths present all the phenomena ot 

 nutrition, the fundamental characteristic of life. 



In the living organism nutrition results in growth, 

 development, and evolution. Growth and development also 

 follow the absorption and fixation of aliment by an osmotic 

 production. An osmotic production grows, its form develops 

 and becomes more complicated, and its weight increases. An 

 osmotic growth may weigh many hundred times as much as 

 the mineral sown in the solution, the mother liquor losing a 



