North American Eastern Tertiary — Meyer. 89 
'Tertiary territories, like the Paris", London or Mayence basins, 
-are insignificant spots. Owing to the small amount of work 
•done in this large field this formation is comparatively unknown. 
While the states whose territory is constituted by older forma- 
tions are mostly well studied and mapped. The Tertiary states, 
if this expression may be used here, stand generally in these 
respects behind some western territories. 
The eastern Tertiary may be divided into two groups; one, 
the Atlantic group, comprising the Atlantic states proper from 
New Jersey to Florida, the other, the Gulf group, including 
the states from Alabama to Texas. In the first group the 
younger Tertiary formations are extensively developed, while 
the marine beds of the Gulf group are Old-Tertiary. We may 
consider first this Gulf group. 
The Gulf Group — Our knowledge of the palseontological 
•condition of the Gulf group is unsatisfactory. There are in- 
deed several hundreds of species of marine invertebrates known 
from it, in the description of which quite a number of authors 
have participated — S. G. Morton, T. A. Conrad, I. Lea, H. C. 
Lea, W. M. Gabb, R. P. Whitfield, A. Heilprin, O. Meyer, T. 
H. Aldrich, D. W. Langdon, H. B. Geinitz. Yet there is no 
doubt that many hundreds more occur in it, which are still 
•unknown. Almost every new localit}- fuiniishes new species, 
and the most thoroughly explored places yield new forms, when 
again examined. It is, however, less the quantity of known 
palieontological material, which is unsatisfactory, than the 
quality, and the writer, after having examined nearly all the 
existing type-specimens of the Old-Tertiary may be pardoned, 
when he calls this part of science an Augean stable. At present, 
however, thanks to the energy and liberality of Mr. T. H. 
Aldrich, there is suflicient reason to expect, that the paleontolgy 
of the eastern Old-Tertiary will be soon thoroughly worked up. 
Our knowledge of the stratigraphy of the Gulf Tertiary is 
still worse, inasmuch as the first foundations of it are uncer- 
tain. The marine Tertiary occupies a territory extending nearly 
parallel to the gulf of Mexico through Alabama, Mississippi, 
Louisiana and Texas. In the last three states and apparently 
also in western Alabama this Tertiary is separated from the 
gulf by a formation composed of sandstones, massive clays, etc., 
