166 The American Geologist. March, i890 
have been instrumental in bringing about. It will do much 
to settle our geology on a true basis." In another letter, 
dated Albany, August 29, 1860 : "It seems something wrong 
took place in the publication of professor Heer's letter to you 
in Sill7nan''s Journal. I thought that professor Dewey would 
state exactly how that letter came into my hands, for I gave 
him your letter also". Finally in another letter dated March 
12, 1859, Dr. Emmons says : "I am much obliged to you for 
your work on the Geology of North America. It was of great 
service to me as I availed myself of all the kind expressions 
relative to me. It saved, I think, the survey of North Car- 
olina from going by the board. * * * * Shall we, in 
this country, have the fortune to be reinforced by your 
future residence here? We are sadly off for men of the true 
stamp. I have heard professor Henry express his regrets at 
what has taken place here in regard to yourself, who I know 
entertains for you the highest respect." 
In resume, in 1849, when on the field near Richmond, I 
parallelized the coal beds there, with the Keuperian coal of 
eastern France, Switzerland and Wiirtemberg ; regarding the 
upper part of the series of Richmond as the equivalent and 
homotaxis of the whole Keuper or Upper Trias. After my 
two notices of 1849 and 1853, in which I hesitated to refer 
those rocks to the Keuper or the Lias, on account of fossil 
fishes considered as Liassic by Agassiz, I took a definite con- 
clusion in 1854, after my return from my exploration by the 
35th parallel of latitude, and placed them as the upper part of 
the Trias, or American Keuper of the Atlantic states. 
Without knowing my researches, nor publications. Dr. 
Emmons, first in 1852, and afterward in 1857, came to the 
same conclusion, referring the coal formation of Richmond 
and North Carolina to the Dyas and Trias. He found two 
series of strata, the Chatham series and the coal of Dan river, 
5,000 feet of thickness in North Carolina, containing fossil 
animals and plants indicating great lacustrine and brackish 
water deposits, analogous and of the same age as the upper 
Dyas and the whole Trias of Germany, England, France and 
Russia. 
In comparing our publications in 1860, we agreed on the age 
of the series of strata of the coal formations of the vicinity of 
Richmond and North Carolina, regarding them as the equiva- 
