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SGIENGE. 



[N. S. Vol. VII. No. 178. 



existence; 2/ is the complex and instable 

 chemical union of the elements, set up in 

 anabolism, which represents a definite 

 quantity of potential chemical energy, that 

 may be set free when the substance falls 

 back into the more stable equilibrium of its 

 previous condition, by processes of katabol- 

 ism, or final decay. 



C^ In Development x is the vitalized pro- 

 toplasm and other forms of the organized 

 material basis of the organism ; and y is the 

 differentiation of cell, tissue and organ, or 

 what, in general, is described by the term 

 organization of the body of the organism. 



C. In Evolution x is the individual or- 

 ganism, at any particular moment of its 

 existence, which lengthens out by processes 

 of generation into a series of successive in- 

 dividuals ; and y is variation, when a single 

 individual is considered, or divergence, 

 when the series is considered, of both form 

 and function, and results in ' modification 

 of characters ' and ' origin of species.' 



The genetic phenomena in these three 

 categories form a series in which y of the 

 first becomes x of the second, y of second 

 becomes x of the third ; and thus y of the 

 third seems to be the direct outcome of the 

 matter taken in and appropriated in the 

 metabolic process at the beginning of the 

 series. This inference would follow were 

 it not for a second fact, viz.: that the first 

 group of phenomena never (according to 

 present knowledge) takes place except when 

 the matter flows into a living organism. 

 This fact proves that the matter, excejit for 

 the action of the living organism, would not 

 metabolize, but would be simply aggregated 

 to the previous mass of the organism, in the 

 same condition as when it met the organism. 

 Thus it becomes evident that metabolism is 

 a function of the organism upon receiving the 

 increment of inert matter ; and going on to 

 the second categorj' we likewise discover 

 that the organizing of the matter is a func- 

 tion of the living organism ; and still fur- 



ther on it is evident that the variation and 

 the divergence of characters in evolution 

 are functions of living organisms alone. 



In each case the phenomena are alike for 

 like conditions of previous living organism, 

 but they are unlike for like conditions of 

 both the material medium and the ma- 

 terial additions derived from without the 

 organism. Hence it is proper to say that 

 the determination of the genetic phenomena 

 may be traced directly to a previous living 

 organism, always present and active, and 

 not to the conditions of the materials with- 

 out at any particular moment of the process. 



NATURE OF AN ORGANIC BODY. 



This brings us to the consideration of another 

 2orohlem : Wliat hind of a thing is this organic 

 body which exhibits such genetic phenomena f 



Tait tells us that " In the physical uni- 

 verse there are but two classes of things, 

 matter and energy." He has further elab- 

 orated the proposition in the following 

 words : " Energy, like matter, has been ex- 

 perimentally proved to be indestructible 

 and uncreatable by man. It exists, there- 

 fore, altogether independently of human 

 sense and human reason, though it is known 

 to man solely by their aid." 



Again, in the Newtonian formula we have 

 the following proposition about matter in 

 general, viz.: " Everj^ body continues in its 

 state. of rest or of uniform motion in a 

 straight line, except in so far as it is com- 

 pelled by force to change that state." 

 With these definitions in our minds, what 

 answer can be given to the question : Is a 

 living organism an inert body or mass of 

 matter ? and second : Is its integrity and in- 

 dividuality determined by a compelling 

 force ? In forming a reply we note the fol- 

 lowing particulars : 



1. The matter of a living organism, as 

 well as its form or configuration, is con- 

 stantly undergoing change, while its integ- 

 rity, identity and individuality persist. 



