REVIEW OF THE MODERN DOCTRINE OF EVOLUTION. 229 



fngs ; and this probably consists of several molecules. This nnit 

 has been termed, by Haeckel, the plastidule. The transmission 

 of the bathmic force of one generation to another would be effected 

 by the transmission of one or more living plastidules ; and this is 

 probably precisely what is accomplished in reproduction. The 

 Dynamic Theory of reproduction I proposed in 1871,* and it has 

 been since adopted by Haeckel under the name of perigenesis. I 

 compared the transmission of bathmic force to that of the phe- 

 nomenon of combustion, which is a force conversion transmitted 

 from substance to substance by contact. The recent observations 

 of Hertwig, Biitschli and others, confirm this view. The theory 

 of pangenesis, devised to explain the phenomenon of reproduction, 

 is to my mind quite inadequate. 



III. METAPHYSICS OF EVOLUTION. 



I enter here upon a wide field, over which I can only skim on 

 an occasion like the present. The subject has been already intro- 

 duced by reference to consciousness as modifying movement ; of 

 course, then, if movement modify structure, the latter is influenced 

 by consciousness. The word consciousness was then, and is now, 

 used in its simplest sense, viz. : as synonymous with physical 

 sensibility. Its lowest and most usual exhibition is the sense 

 of touch ; the special senses, taste, sight, etc., are higher forms, 

 while thoughts and desires are organized products of the same raw 

 material. Consciousness can not be denied to many of the inferior 

 animals ; indeed, if we grant it to any, we must admit that it is 

 displayed at times by even the lowest Protozoon. That these 

 humble creatures should possess it, is apparently quite as proba- 

 ble as that the very similar bioplasts of the brain of man should 

 be its seat. 



Consciousness alone is not a sufficient basis for the develop- 

 ment of mind. For this, one more element is necessary, and that 

 is, memory. Impressions made by the environment are registered, 

 and soon cease to be present in consciousness. Under the influ- 

 ence of association the impressions return to consciousness. Asso- 

 ciations are those of place, of the order of time, and of similarity 

 or difference in various qualities, as size, color, or any other physi- 

 cal features. Experiences of these qualities are to all conscious 

 beings either painful, indifferent, or pleasurable. When associa- 



* " Method of Creation," 1871. 



