338 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser. 



The Middle Trias or Dinaric Series. 



The Dinaric series is the equivalent of the Alpine and 

 German Muschelkalk, and for this division of the Trias the 

 Mediterranean region furnishes the world's type, and the 

 subdivisions, Lower, Middle, and Upper Muschelkalk, are 

 used wherever deposits of Middle Triassic age are iden- 

 tified. It does not follow that breaks in the series will occur 

 at the same horizon in different regions, and in fact they 

 do not. 



Waagen and Diener (27) proposed to divide the Dinaric 

 series, or Muschelkalk, into two stages, a lower or Hydas- 

 pic, known only in the upper Ceratite limestone of the Salt 

 Range; and an upper, or Anisic, most characteristically 

 developed in the Alpine province. But Dr. A. Tornquist 

 (35 and 36) has shown that the Fassanic beds, Buchenstein 

 and Marmolata formations of the southern Alps, contain 

 Ceratiles nodosus and other characteristic species of the 

 Upper Muschelkalk of the Germanic Trias, and must 

 therefore be classed in the Dinaric series. In all probability, 

 then, the Hydaspic stage becomes merely the equivalent of 

 the Lower Muschelkalk. During this stage the connection 

 between the Mediterranean and the Asiatic regions does not 

 seem to have been intimate, for the faunas are entirely dis- 

 tinct. But at this time the genus Dinaritcs, which abounded 

 already in the Lower Trias in the Mediterranean and Arctic- 

 Pacific regions, appeared for the first time in the Salt Range 

 province. Also the genera Aci'ochordiceras and Httngarites 

 made their entrance into the Arctic-Pacific and the Amer- 

 ican regions, while they existed in the Oriental and Medi- 

 terranean regions in the Lower Trias. Tirolites, Ptyckttes, 

 Balatonites, and Parapopanoceras appear for the first time 

 in the American region. 



In the middle Muschelkalk a closer relation was estab- 

 lished between the European and the Asiatic faunal regions, 

 and a few species are common to these. The zone of 

 Ptychites rugifer may be taken as interregional, and a basis 

 of comparison of the separated faunas, for a somewhat 



