DIENEE: TRIAS OF iHE HIMALAYA^. 
It has been demonstrated by J. P. Smith, that the Tethys of the 
Lower Trias extended from India to the W estern States of North America 
across the entire Pacific Ocean. There are some strong afhnities 
between the Lower Triassic faunae of the Himalayas and Eastern Siberia 
on one side and of California and Idaho on the other, but an attempt 
to correlate the stratigraphical subdivisions on either side of the Pacific 
Ocean meets with considerable obstacles, owing to the difEerences in 
the geological history of the two regions. 
In America the oldest fauna of Lower Triassic age is concentrated 
in the Meekoceras beds of California and Idaho. According to J. P. 
Smith 1 this fauna shows an intimate relationship to that of India and 
Eastern Siberia (Ussuri district) and none to the fauna of the 
Mediterranean region. After the deposition of the Meekoceras beds 
an invasion of Mediterranean forms took place. The -fauna of the 
Tirolites beds, which is characterised by this incursion of Mediter- 
ranean types — ^three European species of Tirolites, one of Dalmatites 
and one of Dinarites — is decidedly the same as that of the upper 
Werfen or Campil beds in the Alps. But this incursion was only 
sporadic, for in the overlying Columbites beds there is an assemblage 
of Mediterranean, Asiatic and autochthonous forms. 
All those three horizons of the Lower Trias are exposed in Idaho 
in a continuous section in Paris canyon, the Columbites beds occurring 
15 metres above the Tirolites horizon and 90 metres above the main 
layer of the Meekoceras beds. 
importance of the association of Mediterranean, Pacific and Indian elements 
in this fauna. 
The results of G. v. Arthaber's examination of these new materials have not 
yet been published, but I owe to Prof. v. Arthaber the valuable and interesting 
communication, that both the Indian and Pacific elements far exceed the Medi- 
terranean ones. Columbites and Pseudosageceras are represented in large numbers 
in the new collections. The local iieculiarities are rather remarkable. A striking 
character is the presence of a primitive stock of generalized forms, which might 
be considered as radicles of different tyjjes of Ceralilidu: and of Monophyllites. 
A primitive ancestor of the genus Tropites deserves special mention. The presence 
of the genus Japonites, which hitherto has not been found in beds older than 
Muschelkalk, forms a sharp contrast with those generalized forms which give 
a rather old aspect to the Lower Triassic fauna of Albania. 
1 A. Hyatt and J. P. Smith : Triassic cephalopod genera of North America, V. S. 
Geol. Survey, Profess. Pap. No. 40, Washington, 1905 — J. P. Smith : The strati- 
graphy of the Western American Trias. Sonderabdr, aua Koenen Festschri ft, 1907, 
pp. 377-394. 
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