306 THE PHENOMENON OF 



old structure, in renewed construction of the organism. 

 The examination of Cell-formation leads back, therefore, 

 in all the wider circles of Rejuvenescence, into the plastic 

 life of the plant, nay, it leads us even beyond the circle of 

 the individual development and the related close family 

 union in the sprouting vegetable stock, to the true 

 reproduction of plants, which presents itself, in con- 

 nection with the less perfect renovations of Cell-formation 

 in the preceding circles of development, as the most 

 decided and freest reconstruction of the cell, and at the 

 same time as the recommencement dating itself furthest 

 back, the most complete Rejuvenescence. As in the 

 formation of the individual, each new stage arises with 

 a new section of Cell- formation, so also does the transi- 

 tion of one individual developmental process to another ; 

 and thereby the intercalation of the individual life in the 

 compound life of the species, in every case, takes place 

 through a new impulse in the cell-formation. Con- 

 sequently Cell-formation is not merely the commencement 

 of, and the means to, the production of subordinate 

 tissues ; it is, at the same time, through the law of alter- 

 nation of generations, subordination and serial arrange- 

 ment, prevailing in its progressive renovation, the com- 

 mencement of every comprehensive complication in the 

 organism of the plant, of the single organ as of the 

 special stage in the series of organs, of the single lines of 

 development or the subordinate axes of the vegetable 

 stock, as of the individuals becoming developed into 

 separate stocks. Thus the consideration of the Cell- 

 formation in the Rejuvenescence of the Individual is most 

 intimately connected with that of the Rejuvenescence of the 

 Species ; indeed so intimately that the boundary between 

 the two is often difficult to draw, as we have seen in the 

 foregoing pages, at the lowest stage of the Vegetable 

 Kingdom, in a portion of what are termed Unicellular 

 plants, plants with generations of vegetative cells separ- 

 ating from each other (p. 125, &c.) And, just as we see 

 here, at the lowest stage, the cell-division (p. 233) else- 



