CLASSIFICATION OF MARINE TRIAS 387 
a sea stretched through southern Europe, eastward to the Hima- 
layas; this was years ago called by Neumayr the ‘Central 
Mediterranean,’ and Suess? has recently proposed for it the 
name Thetys. 
Along the western borders of the Thetys were deposited the 
Triassic sediments of the Alps, Spain, southern Italy, the Bal- 
earic Islands, Sicily, Hungary and the Balkan Peninsula. This 
region was named by Mojsisovics* the Mediterranean Trias prov- 
ince. Most of the faunas of the Trias, from near the base to 
the top, are represented in this region. 
To the east the Thetys spread out to the waters of the Indian 
region, in which the sediments of the Himalayas and the Salt 
Range accumulated. The Indian waters joined on the north, 
east, and south with the great Arctic-Pacific Trias ocean, or 
Arctis of Mojsisovics, along the borders of which were deposited 
the sediments of northern and eastern Siberia, Spitzbergen, Japan, 
Rotti, New Zealand, New Caledonia, Peru, and western North 
America. But in this ocean region there were many provinces 
as yet unknown, or only vaguely defined. 
The provinces themselves, and even the greater geographic 
regions, were not constant during the entire Trias, for some of 
the genera show an entirely different distribution during succes- 
sive epochs. And even where faunas are common to different 
regions or provinces they do not always occur at the same hor- 
izon. Mojsisovics? has shown that during the Lower Trias, or 
Scythic series, the Mediterranean province was cut off from the 
Indian and the Arctic-Pacific waters, since it had elements that 
were lacking in those regions, as 77rolitine, and lacked many 
others that were plentiful in the Oriental waters, as Ovoceras, 
Ophiceras, Gyronites, and Flemingites. Also many faunal elements 
that were exceedingly plentiful in the one region were rare in 
the other. Mojsisovics* further noted that during the Dinaric 
™ Nat. Sci. Vol. II. No. 13, March 1893. 
2 Abhand. K. K. Geol. Reichsanstalt Wien, VI Band, II Haelfte, Das Gebirge um 
Hallstadt, I Abtheil, Il Band, p. 811. 
3Arktische Triasfaunen, pp. 143-155. 4 Loc. cit. 
