186 General Notes. [ March, 
Did the communication take place on the side of the Pacific? There 
are many mysteries still to be solved. The fine researches of American 
savants open new horizons for our thoughts; being so distant they still 
appear a little misty, but doubtless they will come forward one day and 
inaugurate the great era of paleontology. 
Will you please, dear friend, accept the expression of my most sincere 
sentiments. — AtBert Gaupry, Professor of Paleontology in the 
useum of Natural History. 
Professor Hayden: Dear and Honored Sir,— For many months I 
have lived in communication of thought with you, and the happy interme- 
dium of our common friend, Lesquéreux, binds us to each other. Your 
name now is so widely known in Europe, and it is so intimately connected 
with the splendid discoveries which paleontologists owe to your explora- 
tions, that I have double pleasure in writing to you. We watch atten- 
tively the results of your undertaking, and, for myself, I may say that 
the rich harvest of Cretaceous and Tertiary fossil plants gathered under 
your direction have opened before me such broad horizons, that I am 
never tired of considering them. I have successively received the pub- 
lications, reports, and fine maps recently published, — thanks to your per- 
severance. I offer you my most sincere wishes for the continuation of 
your work. 
The richness of your deposits is incalculable, but it does not surprise 
me, and I believe that you will be able greatly to increase your treasure 
by new researches. Here in Europe, upon a cut-up continent which 
for a long time has rather been an archipelago than a wide region, we 
have small lacustrine formations, corresponding with other lakes of 
small extent, also, and these formations are often very rich in fossils. 
But this abundance is restricted, though real, for the extent of the for- 
mation is proportional to that of the land surface wherein they are dis- 
tributed. But in America all is on a very large scale: the rivers, the 
plains, the lakes, the mountains, the frame itself is grand ; and this aspect 
is the result of ancient causes which have influenced the nature and the 
thickness and extent of the formations. 
You will therefore discover in these deposits (ours are unimportant in 
comparison to them) an inexhaustible mine of fossil wonders, and be 
able to rebuild in its integrity the transition age, from the Cretaceous to 
the Tertiary, a serial link destroyed in Europe by a succession of blanks. 
Nevertheless in Provence even, and quite near Aix, we have a small 
agglomeration of what is known under the name of Lignitic of Felveau, 
which my friend Matheron has determined as the equivalent of the fresh- 
water upper Cretaceous formation (Santonienne) which passes by de- 
grees in its upper part to strata incontestably of Tertiary age. Regret- 
fully, however, these intermediate layers which would be most interest- 
ing to know well are very barren of fossils, while the lignitic themselves 
have a lacustrine fluviatile fauna, and also brackish deposits extremely 
