344 THE LAW OF EVOLUTION CONTINUED. 



eralogists nor meteorologists have yet enumerated, and the 

 molten globe out of which it was evolved, the contrast in 

 heterogeneity is sufficiently striking. 



119. The clearest, most numerous, and most varied 

 illustrations of the advance in multiformity that accompa- 

 nies the advance in integration, are furnished by living or- 

 ganic .bodies. Distinguished as we found these to be by the 

 great quantity of their contained motion, they exhibit in an 

 extreme degree the secondary re-distributions which con- 

 tained motion facilitates. The history of every plant and 

 every animal, while it is a history of increasing bulk, is also 

 a history of simultaneously-increasing differences among the 

 parts. This transformation has several aspects. 



The chemical composition which is almost uniform 

 throughout the substance of a germ, vegetal or animal, 

 gradually ceases to be uniform. The several compounds, 

 nitrogenous and non-nitrogenous, which were homogene- 

 ously mixed, segregate by degrees, become diversely pro- 

 portioned in diverse places, and produce new compounds by 

 transformation or modification. In plants the al- 



buminous and amylaceous matters which form the substance 

 of the embryo, give origin here to a preponderance of 

 chlorophyll and there to a preponderance of cellulose. Over 

 the parts that are becoming leaf-surfaces, certain of the 

 materials are metamorphosed into wax. In this place starch 

 passes into one of its isomeric equivalents, sugar; and in that 

 place into another of its isomeric equivalents, gum. By sec- 

 ondary change some of the cellulose is modified into wood; 

 while some of it is modified into the allied substance which, 

 in large masses, we distinguish as cork. And the more nu- 

 merous compounds thus gradually arising, initiate further 

 unlikenesses by mingling in unlike ratios. An animal- 



ovum, the components of which are at first evenly diffused 

 among one another, chemically transforms itself in like 

 manner. Its protein, its fats, its salts, become dissimilarly 



