GENERAL CONCLUSIONS 47 



always active substances though it may be only the 

 albuminoid matter of the protoplasm. 



On the other hand, all phenomena of nutrition are 

 protoplasmic, that is to say the food of any cell, whatever 

 that food and whatever the cell, must begin by forming 

 a part of the protoplasm before being consumed or 

 utilized. From this we understand that the two tar- 

 trates do not lend themselves with the same facility 

 to this combination, or, that once combined, they have 

 different stabilities. Thus it is that the active bimalate 

 unites with the right-handed bitartrate to give a crystal- 

 line combination unrealizable with the left-handed 

 bitartrate. Thus it is that the two tartrates of quinine 

 are quite dissimilarly resistant to the action of heat. 



A living cell appears to us, therefore, as a laboratory 

 of dissymmetrical forces, where a dissymmetrical pro- 

 toplasm acting under the influence of the sun, that is to 

 say, under the influence of dissymmetrical exterior forces, 

 may preside over quite varied actions, may manufacture 

 in its turn new dissymmetrical substances which add 

 to or take away from its power, may utilize one of the 

 elements of a paratartaric acid without touching the 

 other, may manufacture crystallizable sugar at one 

 moment to consume it at another, make reserve foods 

 today and exhaust them tomorrow, in brief, may show 

 the marvelous plasticity which we know to be char- 

 acteristic of it, and all that very simply, without any 

 stir, by means of very small deviations of forces under 

 dissymmetrical influences. 



The nature of the albuminoid substance of each cell, or, 

 to speak more generally, the direction of the dissym- 

 metry of one or several of the elements of its protoplasm, 

 exerts thus on its functions and therefore on its develop- 

 ment, an influence of the first order, the mechanism 

 of which, obscure up to this tune, is a little clearer when 



