64 
PALAEONTOLOGY OF NEW-YORK. 
the Gulf of Mexico, belong to the same limestones which in the Coal mea¬ 
sures of Ohio and other Western States, appear in bands of a few feet in 
thickness. 
From the Report of Captain Stansbury*, we learn that extensive mourn 
tains, or even ranges of mountains, in the neighborhood of the Great Salt 
Lake are composed of this Upper Carboniferous limestone. Some of these 
mountains have an elevation of three thousand feet above the plain ; and, 
though quite unaltered in their condition, rest upon metamorphic strata, 
similar in character to those of the Appalachian range. This limestone has 
been identified by its fossils in the neighborhood of Fort Laramie: it is 
known from observations along the line of the United States and Mexico 
Boundary Survey; it is also known from collections made near Santa Fe, 
New-Mexico, at the Pecos village, the Mogollon mountains, at El Paso on 
the River San Pedro, in the Gaudaloupe mountains, and many other locali¬ 
ties. From the massiveness and compact texture of some specimens, and the 
subcrystalline character of others, we are prepared to learn that this rock 
has become extensively developed in that region. The shaly beds which 
accompany this limestone in its more northern and eastern localities, and 
are there often more conspicuous than the limestone itself, have so far 
diminished that they form no marked feature in the topography; nor 
has this character been shown in any of the sections of strata which I 
have seen from that region. 
It is either at the base of this formation, or associated with the lime¬ 
stone itself, that we are to look for productive Coal measures; but up to 
this time, we have no positive information that coal has been found in this 
association in the northwestf. Farther to the southwest, the occurrence of 
coal has been mentioned by several explorers of that region. Several spe¬ 
cimens of coal accompanied the collections made by the naturalists of the 
United States and Mexican Boundary Survey, but these were not accom- 
* Stansbury, Expedition to the Great Salt Lake, 1852. 
t The collections made by Captain Stansbury, in his Expedition to the Salt Lake, contain some slaty 
coal and shale; and the occurrence of Sigillaria and Catamites is mentioned in the journal of the natu¬ 
ralist accompanying the expedition. No fossils of this character were preserved in the collections, and there 
may still remain some question in regard to this matter, until we have farther information. 
