612.8 333 



Artificial Formation of a Rudimentary Nervous 



System 



IN my work " L'origine des individus et la construction de 

 l'organisme par les conditions internes " 1 I put forth a 

 mechanical theory of organisation according to which the internal 

 order of beings and their embryological evolution was supposed to 

 be the result of nutritive conditions solely. I admitted the principles 

 regarding inheritance as a consequence of present causes proposed 

 by Delage, and supported his statement with many arguments, but 

 I have of late been induced to consider the whole question from a 

 rather different point of view. There are, in my opinion, no germin- 

 ative plasma and no mysterious principles in the pronucleus, the 

 composition of which cannot have been modified by the mutilations 

 endured by certain organs of its progenitors. The Monads, the 

 Protists of early geological times, evolved into superior mammals 

 without their having any tendency, marvellous property, germinative 

 plasma or catalytic excitants of glandular origin within themselves. 



The internal and external conditions, that is, the agents of pro- 

 gress in the mechanism of nourishment, have doubtless been the 

 efficient causes of an evolution still more astonishing than that of 

 human ovules. Moreover, the study of cellular genealogy, grafts, 

 regeneration, monsters and atavisms obtained by a diminution of 

 nutrition, etc., has demonstrated that there is naught but mechanism 

 more or less obscure and complicated. But the supreme question 

 concerning the origin and functions of the nervous system will be 

 forever a source of impossibilities and. embarrassment. 



I. There are no essential differences in the vibrations of more or 

 less viscous liquids be they organic or inorganic, for instance : 

 gelatine with glycerine, Limax mucus dissolved in acetic acid, 

 albumen of egg, water, mercury or neuroplasm. 



II. The question concerning the origin and functions of the 

 nervous system might be considered as a mechanical problem requir- 

 ing a laborious solution. 



Experiments and comparisons. — Pour in a plate a small 

 quantity of mercury whose fluidity has previously been diminished 

 by the addition of a slight proportion of lead: this will serve the 

 1 Sociedad Cientifica " Antonio Alzate." 1898. 



