432 BIOLOGICAL PHYSICS 



of the food supplied to our bodies, as it assimilates them 

 during the metabolic analysis and synthesis involved in 

 the process of nutrition, and evolves the true life of the 

 tissues, we have already to some extent dwelt ; the 

 phenomena displayed in the life of the uni-cellular, multi- 

 cellular, and the voluntarily controlled organism, we have 

 also endeavoured to describe. We, therefore, now would 

 consider the voluntarily controlled, or highest, type of life, 

 in its origin, graduated continuance, and independent 

 existence, as a process of evolution from a multi-cell 

 parentage, through the contact and commingling of vitalised 

 materials prepared and shed vitalised, not de-vitalised 

 by that parentage for perpetuative purposes. This evolu- 

 tionary process of parental genesis, or embryonic origin, 

 growth, adult fulness of development, and senile decay, re- 

 presents, in one individual organism, the stages of develop- 

 mental evolution of living forms in general. Thus, 

 the life of the individual voluntarily controlled organism 

 is begun in uni-cellular fashion, just as the primitive 

 uni-cellular organism is begun, and continues ; thus 

 also the life of the multi-cellular, but non-differentiated, 

 or sympathetically innervated, organism is paralleled by 

 the pre-systemic nervous system bearing stage of the 

 evolution of organic life forms in general, while the last 

 stage of fully developed systemically innervated organisa- 

 tion of the individual organism corresponds to the 

 concluding division of the animal kingdom, in the character 

 and manner of its innervation. 



Life, therefore, as observed in the individual members 

 of the systemically innervated creation, and as traced by 

 the aid of palaeontology, throughout the long vista of 

 once living forms interred in the geological strata of the 

 earth's crust, as well as observation of the at present 

 existing fauna and flora of the globe, is found to be one 

 in type, in sequence of organic changes and events, and 

 in the character and intrinsic nature of the organic pur- 

 poses subserved by these organic changes and events. 



Thus man himself, as the highest type and example of 

 the life forms that have descended, or rather ascended, 

 from the first created living unit, and have peopled the 

 ever-changing surface of the earth, its aqueous depths, 



