CENOZOTC (marine) : NOTE. 281 
faunal features go, and much less justified than would be one be- 
tween Eocene-Miocene on the one hand and Pliocene-Quaternary 
on the other, only one does not like to consider one's self, nor yet 
wishes to be considered, anything so uncivilized as a Tertiary 
creature." 
Dr. J. S. Newberry writes : 
" In answer to your question about the retention of the subdi- 
visions of Lyell, I would say that it seems to me that we are 
hardly ready to make the change that is apparently inevitable. 
When others have done in the States of Texas, Louisiana, Geor- 
gia, etc., in the Tertiary belt, what you have done for Alabama, 
or what would be better, if you could carry a line of observation 
over all that belt, then I think we would have the data for a 
change and substitution. At present Lyell's names are a conven- 
ience, but for America they must be only temporary. I do not 
quite agree with Prof. Heilprin as to the expediency of merging 
the Quaternary with the Tertiary. We all recognize the fact 
that the stream of life, like that of time, has flowed on uninter- 
ruptedly, and our subdivisions of geological history must be 
matters of convention and convenience. We find, at various 
places in the geological column, evidence of great physical 
changes; breaks which are not universal, but sufficiently marked 
in the structure of a continent to serve as division lines. The 
record of the Ice Period is one of these, and it has seemed to me 
to be convenient to use it as a separation between what may be 
considered distinct chapters in the geological history of the North- 
ern Hemisphere. This subject will present itself under different 
aspects to the paleontologist and the physico-geologist, and it 
seems to me that we cannot make the views of either our sole 
guides." 
Prof. R. P. Whitfield is of opinion, as regards the status 
of the Quaternary, that we need a name by which to designate 
the glacial and post-glacial formations, which shall be absolutely 
distinguishable from names applied to those preceding that great 
change, even if the change was not universal or only extended to 
the northern half of the hemisphere. Still it was perhaps as 
nearly universal as any great change that ever occurred and fully 
as great. If we recognize a Silurian System, Devonian or any 
