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770 STRATIGRAPHICAL GEOLOGY. — [Boox VI. 
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The lower division of the Alpine Trias ranges through nearly the — 
whole mountain-chain, presenting everywhere the same general petro- 
graphical and paleontological characters. Hence it has been an 
invaluable datum-line from which to unravel the complicated structure 
of that region. 
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North America.—Rocks which are regarded as equivalent to the © 
European Trias cover a large area in North America. On the Atlantic — 
coast they are found in Prince Edward’s Island, New Brunswick, 
and Nova Scotia, in Connecticut, New York, Pennsylvania, and North 
Carolina. Spreading over an enormous extent of the western territories, 
they cross the Rocky Mountains into California and British Columbia. 
They consist mainly of red sandstones, passing sometimes into con- — 
glomerates, and often including shales and impure limestones. A> 
distinction may be drawn between the system as developed in the 
eastern and central parts of the continent on the one hand and along 
the Pacific slope on the other. In the former wide region the rocks, 
evidently laid down in inland basins like those of the same period in 
Kurope, are remarkably barren of organic remains. ‘Their fossil contents 
include remains of terrestrial vegetation with footprints and other traces 
of reptilian life, but with hardly any indications of the presence of the 
sea. 
The fossil plants present a general facies like that of the European 
Triassic flora, among them cycads, including some of the European 
species of Pterophyllum. Ferns (Pecopteris, Neuropteris, Clathropteris), 
calamites, and conifers are the predominant forms. The fauna is 
remarkable chiefly for the number and variety of its vertebrates. The 
labyrinthodonts are represented by footprints, from which upwards of 
fifty sp-cies have been described. Saurian footprints have likewise been 
recognized; in a few cases their bones also have been found. Some of 
the vertebrates had birdlike characteristics, among others that of three- 
toed hind feet, which produced impressions exactly like those of birds. 
But as already remarked, it is by no means certain that what have been 
described as ‘‘ ornithichnites”’ were not really made by deinosaurs. The 
small insectivorous marsupial (Dromatherium), above referred to, found in 
the Trias of North Carolina, is the oldest American mammal yet known. 
On the Pacific slope, however, a very different development of the 
Trias occurs. The strata are estimated to attain a thickness of some- 
times as much as 14,000 or 15,000 feet. They contain distinctly marine 
organisms, which include a mingling of such Paleozoic genera as Spirifera, 
Orthoceras, and Groniatites, with characteristically Secondary forms, as 
ammonites (Ceratites Haidingeri, Ammonites ausseanus, &c.) and bivalves of 
the genera Halobia, Monotis, Myophoria, &c. 
Asia.—The Trias has a wide extension in this continent. Strata 
with Ceratites and Orthoceratites occur in Beloochistan, and in the Salt 
Range of the Punjaub. In northern Kashmir and western Tibet a well- 
developed succession of ‘Triassic formations occurs among the Himalayan 
ranges, sometimes exceeding 4000 feet in thickness. It contains many 
of the same species of fossils as occur in the Alpine Trias. Some of its 
forms are Ammonites floridus, A. diffusus, Halobia Lommeli, Monotis salinaria, 
Megalodon triqueter, while the fresh-water beds (Karharbari) in the 
Gondwana series of India contain. a distinctly Bunter assemblage of 
plants, including Voltzia heterophylla and Albertia (near A. speciosa).} 

' Medlicott and Blanford’s “ Geology of India,” pp. xlvi. 114, 
