358 The American Geologist. June, i890 
and in tlie Nevaclo-Canaclian seas. Those two names indicate, 
with more exactness, the extent of sea waters during the 
Taconic epoch, and are preferable to the use of the Atlantic 
and Pacific oceans of that very remote period, because we are 
unable, in our present state of knowledge, to give any idea of 
their extent in any direction outside of the areas of Acadio- 
Eussia and Nevado-Canada. I shall confine my remarks to 
the Lower and Middle Taconic, leaving the Upper Taconic for 
a special study. 
AcADio-RussiAN LowEE AND MiDDLE Taconic. — In the Aca- 
dio-Russian sea we have the following formations distributed 
at special and rather isolated points, as mere patches and 
remains of vast formations concealed since by the strata of all 
the systems which have been deposited since the Taconic 
period. 
Tabular view of the Lower and Middle Taconic of the Acadio- 
Russian sea. 
IV. Bohemian formation or Paradoxides zone. 
III. Scandinavian formation or Holmia zone. 
II. Esthonian formation or Schmidtia zone. 
I. Newfoundlandian formation. — No trilobite found yet. 
I. Newfoundlandian formation. — It would have been 
better to use the name Terranovian, but Mr. T. Sterry Hunt 
has called in his chemical classification of the crystalline 
rocks, a certain class of them Terranovian, it is true without 
any very definite value as regards superposition, relative age 
or even lithological characters, but which may create confu- 
sion. More recently Mr. C. D. Walcott has used the name 
Terra Nova dimsion for the strata of a part of the peninsula 
of Avalon in Newfoundland, which he has erroneously syn- 
chronized with the Georgia slates of Vermont. ("Position of 
the Olcnellus fauna, etc," Amer. Jr. /Sci., vol. xxxvii, p. 383, 
1889). In order to prevent all confusions and claims of prior- 
ity, and desirous also to maintain in classification the name 
of a country so eminently well fitted to be remembered, and 
which will become more and more the typical area of the 
Taconic system, I propose to use the name JVewfotcndlandian, 
in French Ter7r.netivien, for the first great group containing 
fossils at the base of the Taconic. 
Below the strata containing Paradoxides there exist in 
many places, sandstones, slates, quartzites and even limestone 
bands, sometimes rather thin, but often of great thickness, in 
