4o 
blENER: TRIAS OF 'THE HIMALAYAS. 
Four species of Ophiceras, among them 0. cf. Sakuntala Dien. and 0. cf. 
gibbostim Griesb., together with Meekoceras cf. Hodgsoni Dien., have 
been quoted from the Meekoceras beds of south-eastern Idaho by 
J. P. Smith. 
This learned author correlates the Meekoceras beds of America 
with the Hedenstroemia beds, which, according to his view have been 
placed too high in the column by Diener. But the Hedenstroemia 
beds cannot be regarded as equivalents of the Alpine Seis beds, since 
their fauna is undoubtedly homotaxial with the fauna of the Campil 
beds, as is evident from its affinity to the fauna of Kcira in Albania. 
The presence of a species of Tirolites in the Hedenstroemia beds and 
the persistence of a small number of Indian types in the Columbites 
beds of Idaho are rather in favour of a correlation of the Heden- 
stroemia stage with the higher subdivisions of the American Lower Trias. 
Although there is a great probability of a liomotaxis of the 
Hedenstroemia beds with the whole of the upper divisions of the Lower 
Trias of Idaho, we should not forget that the fauna of the American 
Meekoceras zone contains elements of the Hedenstroemia beds, Meeko- 
ceras beds and even Otoceras beds. This is one of the instances 
demonstrating the difficulty of correlating terranes in widely separated 
areas, although this correlation has been attempted on the basis of a 
large number of fossils either generically or specifically identical. But 
the natural divisions are not the same in India and Idaho and 
therefore they cannot be correlated except in the most general way. 
The development of Lower Triassic rocks near Vladivostok in the 
southern Ussuri district of the coast j^rovince of Eastern Siberia ^ is 
another illustration of the uniformity of the fauna around the Pacific 
Ocean during the Lower Triassic age. The association of genera is the 
same as exhibited in the Meekoceras beds of California and Idaho. 
The ammonites have their nearest representatives in the Meekoceras 
zone of the Himalayas — both Meekoceras Varaha and M. boreale have 
been found in the Proptychites beds of Vladivostok — but the pre- 
sence of a species referable to Ophiceras Sakuntala Dien. indicates, 
perhaps, also a correspondence with the Ophiceras bed of the Otoceras 
stage. 
1 C. Diener : Tiiadische Cephalopodenfaunen der ostsibirischen Kuestenpro- 
vinz. Mem. Com. Geol. St. Pelersbourg, 1895, Vol. XIV, No. 3. 
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