282 REPORT OF THE AMERICAN COMMITTEE. 
other, it is as necessary to designate the time post-glacial by some 
means. The change was fully as great in his opinion as that be- 
tween the Cretaceous and Tertiary. He favors the retention of 
the name Quaternary of equal rank with Primary, Secondary, and 
Tertiary, to include glacial, post-glacial and recent. 
Mr. W. H. Dall writes : 
"In response to your inquiry I can only say that the further 
I carry my studies of the Tertiary and recent faunae of the Gulf 
and South Atlantic region, the more it is * borne in upon me ' that 
the divisions of the Tertiary for this part of the world, must de- 
pend upon the stratigraphy. The succession of the faunse seems 
to have been even and gradual in its modifications and without 
sharp faunal breaks, those formerly supposed to be so seeming 
less and less distinct as more knowledge is obtained. There is 
quite a sharp distinction between the 'Pliocene' of Tuoraey and 
Holmes, and the recent littoral fauna which is practically identi- 
cal with their Post-Pliocene, 
" The shells of the shores and the Pliocene seem well divided 
by discrepancies. But the off-shore dredgings of the Albatross 
(U. S. Fish Commission steamer) in water of less than 100 
fathoms, show that, outside of the shore-fauna, there is another 
living fauna which is very closely related to the so-called Plio- 
cene and nearer to it than to the living fauna of the beaches. 
There I find Amusium Mortoni, Valuta mutabilis, Janira hemicy- 
clica, Cancellaria vetusta, Venus rugathia, and a host of others 
supposed to be extinct and generally first described as fossils. 
This introduces a wholly new question of distribution into the 
classification of the fossil faunae, but of which we are yet too ig- 
norant to go very far in generalizing." W. H. Dall. 
Prof. Alexander Winchell says : 
"Assuredly, I never conceived the Lyellian divisions, Eocene, 
Miocene, and Pliocene, as possessing systematic value analogous 
to Cretaceous, Jurassic, etc., but rather as comparable with the 
subdivisions of Cretaceous, Devonian, Upper Silurian, etc. 
'Groups' rather than ' Systems ' (in the current nomenclature). 
But I have never conceived ' Quaternary ' as coordinate in its 
scientific significance, with Oenozoic, Mesozoic, etc., but rather as 
coordinate with Eocene, Miocene and Pliocene, — and hence the 
