J. D. Dana— Views of Professor Emmons. 417 
Mather, referring the Taconic System to the “ Citar plain Di- 
vision” of the New York rocks had been sustained by subse- 
quent observations. Further, his “Chemical and Geological 
Essays” published in 1875 (see Title-page) contains the Associa- 
tion address of 1871, and the same remarks on the Taconic. 
Here are twenty-five years of opposition to Professor Emmons, in 
a number of papers, and never once a hint that Emmons agreed 
with him in the Calciferous age of either of the rocks. The 
account of the investigations of Logan and Hall in Dutchess 
County, New York and elsewhere, bearing against the Taconic 
system, as published in this Journal for 1865, has attached to 
it. Dr. Hunt’s name as he was the writer. Dr. Hunt’s opinions 
were not always couched in courteous language. In 1861, he 
makes the Taconic, exclusive of the slates, equivalent of the Cal- 
ciferous, adding: “It remains to be seen whether Dr. Emmons 
can retain, from the wreck of his system, the lower slates as a 
Taconic formation older than the Potsdam.” This sounds like 
““yersecution;”” and the series of papers like ‘persistent war 
waged against Ebenezer Emmons.” Now, the Restatement indi- 
eates for its author a return to the idea of the Calciferous age of 
some of the Taconic rocks.* 
* The continuation of the ‘‘Taconic Question Restated,” to be found in the 
March number of the Naturalist (pp. 238-250), has been published since the 
above was put in type —the number having been received at New Haven April 
13th. Itcalls for no further remarks. But as it will aid in clearing away doubts, 
and give a fuller view as to what have been, as the author expresses it' (p. 248), 
*““my own teachings,” I cite a few more sentences from his papers during the 25- 
year period of opposition, and others from two of those of the subsequent pe- 
riod of agreement. 
Review of the Progress of American Geology, in this Journal, II, xxxi, 402, 1861. 
“The Quebec group with its underlying shales is no other than the Taconic 
system of Emmons. 
“Review of Mr. Barrande, On the Primoridial Zone in North America,” in the 
Canadian Naturalist, 1861, and this Journal, II, xxxii, 427, 1861. ‘Dr. Em- 
mons claims that the whole cf his Taconic system is inferior to the Potsdam 
sandstone, which is the admitted base of the Champlain division, but we have 
already shown that the whole of his system, with the probable exception of these 
slates [the black slates] is of the age of the Calciferous sandrock, the second 
member of that division.” ‘The fossils of the Quebec group show it to be the 
paleontological equivalent of the Calciferous sandrock. The Stockbridge and 
Sparry limestones with their accompanying slates (excepting only 7 “and 8 
[the Taconic slate and black slate]), we conceive to be no other than the Quebec 
group.” 
Address tu the American Association, August. 1871. Salem, 1871.—p. 15, ‘* The 
Taconic system, as defined by him [Emmons] may be briefly described as a series 
of uncrystalline fossiliferous sediments reposing unconformably on the crystalline 
schists of the Green Mountains, and partly made up of their ruins; while it is, at 
the same time overlaid unconformably by the Potsdam and Calciferous formations 
of the Champlain division, and constitutes the true base of the paleozoic column, 
—thus occupying the position of the British Cambrian.” Hence in 1871 the 
author had not made the discovery that Professor Emmons referred any part 
of his Taconic system to the Calciferous. 
History of the Names Cambrian and Silurian in Geology; published in the 
Canadian Naturalist, for April and July, 1872.—p. 36, ‘‘Kmmons, misled by strati- 
graphical and lithological considerations, complicated the question in a singular 
manner, which scarcely finds a parallel except in the history of Murchison’s Silu- 
