320 _ The Taconic Question Restated. [April 
though unsuccessfully and amidst cruel opposition and injustice, 
to uphold those teachings, and to the best of his ability to extend - 
the generalizations of Eaton; in a return to which, as we have at 
last learned, is to be found the solution of the vexed problem of 
American stratigraphy. 
In the tabular view above noticed the writer attempted to intro- 
duce for the first time into American geology the term Ordo- 
vician, proposed by Lapworth in 1879 for the group of strata 
between the proper Silurian of Murchison and the undisputed 
Cambrian of Sedgwick, which, though by the latter named Upper | 
Cambrian, has been alternately called by others Lower Silurian, 
Siluro-Cambrian, and Cambro-Silurian, and includes the Chazy, 
Trenton, Utica, and Loraine subdivisions of the New York sys- 
tem. This name of Ordovician has since been adopted by many 
- British and European geologists, and is now used by Mr. Charles 
D. Walcott, of the United States Geological Survey, whose im- 
portant generalizations regarding the American Cambrian, no- 
ticed in the above volume, pages 624, 625, are given at length in 
his recent work in 1886, entitled “Studies of the Cambrian 
Faunas of North America” (“ Bulletin No. 30 of the Geological 
Survey”), and constitute a precious contribution to our knowledge 
of the North American Cambrian. His table of the succession 
of the Cambrian, with its subdivisions, and the Ordovician, will 
be found on page 44 of that Bulletin." 
1 Since writing the above paper there has appeared in the American Fournal of 
Science for February, 1887, an abstract by Mr. Walcott of a paper read by him in 
January before the Philosophical Society of Washington, in which he puts forth 
Taconian rocks, as maintained by Mather, II. D. Rogers, and C. B. Adams, since 
resuscitated by J. D. Dana, supporting it apparently upon the assumption that certai 
white sandstones carrying Olenellus, found to the eastward of the Taconic ak, 
are identical with the Primitive Quartz-rock of Eaton, the basal division of the 
Taconian, While entertaining the highest regard for Mr. Walcott’s admirable work 
in palzeontology, the writer can see in his TEBE note no sigs for raig the 
usions already set forth in the preceding pages . 
