Hyatt. J 60 [April g, 
iiismeir' ;iii(l tlio clToi-ts of the autlior in a liiiiitt'(I part of the same 
(ield. liuckily the younger men, wlio liave since tested the methods 
of work proposed at tliat time and considered tliem worthy of their 
adoption, have so far found ground for serious criticism only in 
tlie nomenchiture. 
It woukl be too sanguine to expect tliese beatific conditions to 
hxst, but in tlie meantime those who agree upon the main ideas and 
objects of the new school ought to be able to reach common ground 
upon the less imi)ortant details of nomenclature. With the view 
of doing my part towards this desirable end I have written the 
following paper partly in reply to a critical paper by IVIessrs. 
liiu'kman and Bathei- and partly as a new contribution in the same 
field. 
I ])ropose to descrihein a brief way the four different lines of 
research which are usually designated by the jiopnlar terms growth, 
heredity, acquired characteristics, and the correlations of develop- 
ment of the individual (ontogeny), with the evolution of the group 
to which it belongs (phylogeny) ; the object being to explain the 
relations of these to each other and to give adequate reasons for 
the substitution of scientific terms for the popular names heretofore 
used. Since I have to refer to one of the new names before the 
explanation appears in the text, it is proper to state that, instead 
of the study of growth, it is proposed to use the term auxology or 
bathmology ; for heredity, genesiology ; for the origin of acquired 
characters, ctetology ; and for the correlations of ontogeny and 
phylogeny, the term biopiastology. 
Auxology or Bathmology. 
Messrs. Buckman and Bathei", both well known for their origi- 
nal and instructive researches in paleozoology in England, have 
recently in a joint paper under the title of "The terms of auxol- 
ogy"^ justly criticised the nomenclature employed in my papers to 
designate the stages of growth and decline in the individual. 
They have also ])roposed, in view of the correlations which have 
been shown to exist between the transformations that occur in the 
stages of development and define in the individual and those that 
characterize the evolution of the group to which it may belong, to 
desigiuite the study of those correlations by the new terra "aux- 
' Zuol. aiiz., 15, p. 420-421, 429-432, November, ]892. 
