322 
These explanatory remarks serve to show that Ctetology is a | 
branch of research which needs to be isolated from researches upon | 
growth and Genesiology, since it is devoted to the study of the origin | 
of acquired characteristics and therefore necessarily considers all of | 
the internal reactions of the organisms in response to the action of | 
physical forces, as well as the more obscure reactions of structures | 
which are produced solely by (or supposed to be produced by) the 
direct physical or chemical action of external physical forces. 
Bioplastology. 
The separation of Auxology (or Bathmology), Genesiology, and | 
Ctetology show also that the study of the correlations of ontogeny and 
phylogeny to be distinet from either of these, and this branch of re- 
search can be designated by the term Bioplastology from Btoc, life, 
and IlXustic, meaning moulded or formed‘. 
To sum up in a few words the rather ambitious aims of this com- 
paratively new recruit in the army of investigation, it aspires to show 
that the phenomena of individual life are parellel with those of its 
own phylum and that both follow the same law of morphogenesis, 
that not only can one indicate the past history of groups from the 
study of the young, and obviously the present or existing progression 
or retrogression of the type by means of the adult characters of any 
one organism, but that it is also possible to prophecy what is to hap- 
pen in the future history of the type from the study of the correspond- 
ing paraplastic phenomena in the development of the individual. 
Whether these claims are well founded or not the nomenclature 
to be employed is a matter of importance and should be accurate, 
appropriate, and convenient for those who are interested in this work, 
6 Bioplasm, bioplast, bioplastie have already been used by Beale and others 
for the living cell and its contents but the term » Bioplastology « has not been used 
nor have the names proposed by Beale been generally adopted. Ifthey were Bioplas- 
mology would cover the requirements of students of such phenomena and there is 
already in use Plasmology with about the same meaning, and Histology for the 
descriptive side of the study of cellular structures. 
Biogeny has been used in extra scientific literature by Fiske with the same 
meaning as Bioplastology and Haeckel has named the law of embryonie and an- 
cestrai correlation the law of biogenesis, but there is a strong objection to both of 
these. Biogenesis is the name given to the theory of the origin or genesis of life 
from life in contra-distinction to the assumption of spontaneous generation, or abio- 
genesis and has a well established place in scientific literature. Therefore while 
the law of correlation of the stages of development and those of the evolution of the 
phylum, may, if one chooses, be called a law of biogenesis, it is more accurate to 
consider italaw ofcorrelationin Bioplastology or betterstillthelaw 
of palingenesis or regular repetition of ancestral characters which exactly ex- 
presses what the discoverer Louis Agassiz saw and described. 
