Vitality and Organization of Protoplasm. 71 



separately disposed and circumscribed its spatial manifestations may 

 appear to our vision, that it all forms, nevertheless, from start to finish, 

 a unitary ontogenetic process, every phase of which is integrantly con- 

 nected Avith every other. 



FORMATIVE STIMULATION. 



The specific stimuli or inciting agencies that act as inducing causes 

 in the development of the succeeding stages of ontogenetic evolution, 

 and which have been so diligently sought for, now in external, now in 

 internal conditions; these inciting causes are actually found in the im- 

 mediate conditions which give rise to gradual reintegration, and there- 

 with to ontogenetic evolution. The presenceT namely, of specifically 

 assimilable~material coming in contact with the living substance, at 

 whatever stage of its disintegration, germination or fragmentation, nat- 

 urally and necessarily acts as a specific formative stimulus, calling into 

 activity the inherent power of £c.mtegration throug ji complem ental as- 

 similation. Eeeiprocal chemical attraction between the assimilating 

 vital fragment and the assimilable material, due to their complemental 

 jiffinitj are here evidently the actuating agencies. This interpretation 

 flows consistently and harmoniously from the general vital properties 

 of protoplasm, as explained in the former 3v3ction, The power of com- 

 plemental reintegration, after more or less profound disintegration is 

 that which essentially, constitutes protoplasm a living substance. 



By having gained the scientific understanding that assimilation is a 

 process of reintegration on the part of the unitary living substance, and 

 not a new formation of elementary units, it becomes clear that the 

 presence of assimilable or complemental ma,terial will act upon frag- 

 ments of the living substance as a specific and adequate stimulus or in- 

 citing cause whereby reintegration is effected. No need here of any 

 other specific stimuli, provided the conditions of the general medium 

 are otherwise normal and favorable. 



In higher organisms morphological appearances mask to a great extent 

 the unitary formative process. To- gain a clear idea of the far-reaching 

 commotion of the chemical activity and its concomitant mass-movements 

 during ontogenetic evolution, one need only closely watch the phenomena 

 occurring, for instance, within the spherical plasm of a self-dividing 

 Colpoda. The process, though primarily one of self-division, involves 

 *the ontogenetic evolution of a new generation of individuals from germs 

 derived from the parent organism. Here two and often four and more 

 separate germinal centers start into existence within the spherical plasm, 

 and around each the reintegrating work takes its course. It consists evi- 

 dently in an extremely complex process of chemical assimilation and 

 elaboration. For more or less vivid commotion of granules; more or 

 less extensive mass-movements of plasm, with concomitant formation of 

 larger or smaller depurative vesicles, more or less rapidly arising, 

 dwindling and reforming, testify to the intimate chemical nature of the 

 occurrence. The unitary substance of the plasmatic sphere is under- 



