1S93.] -^^l [Rydor. 



matrix is saturated witli inert silicious or calcareous materials. This may- 

 be especially well shown in regard to the wonderfully complex shells of 

 Radiolarians, Foraminifera, the spicules and skeletons of sponges, the 

 shells of the eggs of birds, the calcification of bone and cartilage, etc. I 

 therefore very much question whether there is a single skeletal structure 

 anywhere to be met with, the development of which does not take place 

 in some measure statogenetically. Especially is this true of the configur- 

 ation of the skeletons of such complex objects as Radiolarians, Foramin- 

 ifera, etc., where surface tension cooperating with the process of the 

 gradual statogenetic saturation of the matrix gives to them their wonderful 

 complexity and beauty. While such phenomena as those of the genesis 

 of the heterocercal or upwardly deflected condition of the axis in the tails 

 of fishes, or the downwardly deflected condition of the axis in Ichthyo- 

 sauri are almost purely kinelogenetic, tlie multiplicity of factors concerned, 

 statogenetic as well as ontogenetic and phylogenetic, must always be con- 

 sidered and each given its due weight and importance in achieving the 

 morphogeuetic result. That there is an absolute conflict between sta- 

 togeny and kiuetogeny on the one hand, and of phylogeny and ontogeny 

 on the other, in the case of the development of the ova of multicellular 

 forms admits of no doubt. All metazoa pass through larval stages in 

 which the statical condition of equilibrium of the plasma of the egg is 

 gradually, in a great measure, overridden by the hereditary energies rep- 

 resented by phylogeny and ontogeny. That there still remain traces of 

 the efiects of kinetogeny and statogeny in the adult organism cannot be 

 denied in view of the facts to be derived from the shapes of tissue ele- 

 ments, and even of organs, as the foregoing paragraphs show. 



These few observations and reflections will, I think, at least make it 

 clear that the terms ergogeny, and its forms of kinetogeny and statogeny, 

 are justified, and that they stand for what constitutes a very important 

 part of the machinery of organic evolution, the generality and importance 

 of the influence of which is certainly not less than second to that of phy- 

 logeny and ontogeny. The energy factor or ergogeny left entirely out of 

 consideiation must therefore seriously cripple the symmetry and com- 

 pleteness of anj^ general theory of organic evolution. 



Appendix. 



The introductory chapters to Hasckel's great work on the Radiolaria, 

 forming part of the series of Cliallenger Reports, contains much that is 

 suggestive in relation to the subject of this paper. Also papers by Dreyer 

 and others in the Jenaisclie Zeitschrift, in reference to the ergogenetically 

 developed forms of the tests of Radiolarians, Rhizopodsand Foraminifera. 

 The botanists have long since appreciated t)ie importance of this subject, 

 and Eerthold's rrotoplasmechanik is an especially suggestive work. Sachs 

 lias also contributed to the subject. Much that is suggestive is also to be 

 found in the Principles of Biology of Herbert Spencer, though his facts 



