The Terms of Bioplastoloyy. — Hyatt. 
299 
Ontogenk' Table of Terms iIIi. 
Structural 
Conditions. 
Anaplaeis 
i Haeckel.i 
Metaplasia 
(Haeckel.i 
Paraplasis 
Stages. 
r Embryonic 
I 
Larval or 
young 
I Immature or 
adolescent 
\ Mature or 
/ adult 
Senile or old 
Stages. 
Embryonic 
Nepionic 
Neanic 
Ephebic 
Gerontic 
Substages. 
Several.-' 
^ auanepionic 
• metanepionic, 
/ paranepionic. 
y ananeanic. 
- metaneanic. 
/ paraneanic. 
i anephebic. 
■. metepliebic, 
I parephebic. 
C anagerontic 
-, met a gerontic, 
/ parageroniic. 
Substages. 
.No popular 
name.-. 
The necessity of subdividing the embryonic stage is admit- 
ted and in all probability this really includes several stages 
with their respective substages, hut the discussion of this 
problem must be left t<> the future. The former subdivision 
of the gerontic stage into two substages seems to have met 
with general acceptance, hut the terms remain to be settled. 
Buckman and Bather have proposed catabatic to replace my 
old term clinologic, which is an improvement, but their term 
proposed, hypostrophic, from vnoffTpoq))}' , meaning a turning 
around and back, is not equally good. While this is better 
than the term formerly employed, "nostologic," it is longer 
and not preferable to "nostic" from voGrog\, signifying a re- 
turn in the sense of a journey back to one's home. This par- 
*These stages were enumerated and more or less described under the 
name of protembryo, mesembryo, metembryo, neoembryo, typembryo, 
in my paper on "Values in Classification of stages of Growth and De- 
cline"' and to these Jackson added phylembryo in his 'Phytogeny of 
the Pelecypoda," p. 289,— See "Values of Classification of the Stages of 
Growth and Decline," Am. Nat., Oct.. 1888, and "Genesis of the Arie- 
tidse," Smithsonian Contributions, No. 673, 1889, also Mem. Mus. Comp. 
Zoology, xvi, No. 3. 
+ Neither of these words has any authority for the termination ''ic," 
but unless one can make some such "corruptions" it is often impractic- 
able*to manufacture a consistent set of terms according to the method 
here adopted. It is obvious that scientific convenience occasionally 
requires such heroic methods,and this seems to be a case in which it is 
justifiable. 
If the new set of terms here proposed is adopted, there will be no 
need of employing either "catabatic" or "nostic." These will then be 
superseded by "anagerontic" and paragerontic," or by all three terms 
used for the stages in the table, if the characteristics justify their ap- 
plication. It was necessary, however, to discuss these term6 because 
two distinct 6ets of names have been employed for the subdivision of 
the senile period. 
