I CHAPTER IT. 



OF GENERATION IN THE TWO KINGDOMS. 



GROWTH is only an excess of nutrition, and generation is only 

 an excess of growth. Growth and generation have for cause a 

 superabundance of nutritive materials. This superabundance 

 has for effect first of all to carry the anatomical elements to 

 their maximum volume, then to provoke the formation of new 

 elements. As long as the individual has not attained all the 

 development compatible with the plan of his being, the elements, 

 newly born, remain aggregated to the pre-existent elements. 

 When the limit of growth is attained, when there is no longer 

 room in the organised individual for a new adjunction of histolo- 

 gical elements, the newcomers detach themselves from their 

 organic stem and constitute independent individuals which 

 evolve in their turn. 



Generation is so much a continuous growth, that its processes 

 are identical with or analogous to those of growth. Definitively, 

 in growth as in generation, those processes reduce themselves 

 to two : the process of segmentation and that of genesis, which 

 however can aid each other and combine their action. 



Division (scissiparity, fissiparity, and so on) is observable in 

 the majority of the lowest representatives of the two kingdoms. 

 It is habitually the division into two parts which is then in 

 use, bipartition, sometimes longitudinal as in the vorticels, 

 sometimes transversal, as in the hydrae, the acalephans (Fig. 43). 



