60 Scientific Intelligence. 
r 
face of the te} entirely encased in this concretionary substance 
to the thickness of two or three inches. I propose, however, In a 
subsequent paper, to describe more fully the structure and com- 
osition of these deposits. The eastern edge of this secondary 
asin is formed by the Santa Rosa mountains. On the north 18 
the high land between the Vicksburg and Santa Rosa ranges, an 
the low divide between Divide and Puebla Valleys. Directly 
south of the Bottle Creek range the basin is separated from the 
valley of the Humboldt by a low range of hills about fifteen miles 
north of the latter river. As to its extent farther to the west- 
ward, I have no data. It certainly includes the Black Rock 
Desert, and I think a considerable extent of country still more to 
the south and west.” 
3. “ Lignitie Formation” of the Rocky Mountains.—The second 
part of Dr. Hayden’s Report for 1872 commences with details of 
explorations connected with the Lignitic formations of the Rocky 
Mountains by L. Lesquereux, and is followed by an enumeration, 
with descriptions, of the fossil plants from the same formation and 
from the Cretaceous of Kansas. 
As stated in the letter serving as an introduction to Prof. Les- 
quereux’s report, the arrangement of the paper conforms to the 
directions given by Dr. Hayden for the author’s exploration, namely, 
to follow from the Rocky Mountains in New Mexico, northward 
species, of which sixty-one are considered as new. The Cretaceous — 
flora, too, though explored only at two localities in Kansas, § 
also increased by a comparatively large number of new species 
A number of facts and also some discussions interesting 1 — 
science may be selected from this report for future publication. Ds 
4. Th oon Canadense, and related Paleozoic species ; PY — 
Dr. J. W. Dawson. (From Dr. Dawson’s Annual Address before 
