228 BIOLOGICAL PHYSICS 



invaginated, by meningeal continuations, throughout its 

 entire extent, thus securing for itself effective mechanical 

 protection and support, continuity of proper nervine 

 elements and complete structural isolation, and functional, 

 or dynamic, insulation, so constituting itself the great 

 neuro-dynamic instrument and agency, in the human 

 organism, throughout its systemically innervated extent. 



The viscero-skeletal stage of development and evolution, 

 is represented by the formative process, of surrounding 

 the alimentary segment of the neurenteric canal, with 

 organs, and structures, fitting it for the performance of 

 the digestion, aeration and distribution, of the alimentary 

 materials, to suit the wants of the whole organism and 

 providing an osseous casing for the central nervous system, 

 consisting of brain and cord, and an osseous skeleton, 

 whereby the voluntary musculature is enabled to effect 

 locomotion, and through that, the manifold activities of a 

 living and responsible existence. 



This short recital gives, in brief, but recognisable out- 

 line, the salient features of the process of evolution through 

 which the human body passes, before it begins its down- 

 ward, or involutionary, course, or when aging begins to 

 make itself felt, and to proclaim itself in every feature. 



