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GEOLOGY OF NORTH CAROLINA. 
The most abundant plants in the coal are ferns : but trees also abound 
of very peculiar forms, related to some of the more insignificant tribes 
of the present day, such as the club-mosses, rushes and the like. The 
highest class of plants of the coal age is a species of tree related to the 
pines. Animals also of a higher organization than any found in the pre- 
ceding formations, make their appearance, such as frogs, salamanders and 
other amphibious creatures and reptiles ; hence the designation Amphi- 
bian Age. 
The English and many of the continental coal beds also belong to this 
horizon. They are of great extent in the British Islands, occupying an 
area of some 12,000 square miles, and in some localities, of a thickness of 
many thousand feet. 
PERMIAN SYSTEM. 
The next group in order, the Permian , is scarcely known in this 
country, only a few of its characteristic fossils having been discovered in 
one or two states west of the Mississippi ; where, however, the strata 
containing them are regarded as more properly a continuation of the 
carboniferous, to which they are conformable. 
The preceding systems are grouped together under the general desig- 
nation paleozoic, [ancient life) / on account of the transition to higher 
forms, which is observed in passing to the next series of systems, the Meso- 
zoic, {middle life ), which consist of the Triassic, Jurassic and Cretaceous, 
and are characterized collectively as the Reptilian Age , from the pre- 
dominant type of its animal life. 
TRIASSIC SYSTEM. 
The lowest of these, the Triassic, is represented very scantily on the 
Atlantic slope, being limited to the narrow tracts .of sandstones, with 
shales and conglomerates, so well known in the Connecticut Valley; 
which extends also, with few interruptions, from the Hudson River in 
southeastern Hew York to the upper border of South Carolina. These 
rocks are, however, developed on a great scale in the states west of the 
Mississippi, from Nebraska to Texas and New Mexico, as well as in Cali- 
fornia and the adjoining states; and it is of common occurrence also in 
Europe. The famous brown sandstone, so much used in building in New 
York and elsewhere, is obtained from this formation, mostly in the 
Connecticut Valley ; and the same rock is characteristic of it in North Car- 
olina. But the important feature of it here and in Virginia, is the occur- 
