CORHELATTON OF TTII-^ MTDDLK TRIAS. 
81 
the Lower Trias of Kcira in Albania by G. v. Arthaber.^ Two species 
of Orthoceras — 0. cf. campanile Mojs. and 0. cf. mullilahiatum Hauer — 
are probably identical with Alpine forms. A very interesting type is 
Gymnites depauperatus Dien., the most primitive species of that genus, 
any trace of ramification being absent in its sutural line, which is 
provided with saddles entirely dolichophyllic. 
The most characteristic group of ammonites in the zone of Spirifer- 
ina Stracheyi is the Indian section of Keyserlingiies (Durgaites) which, 
notwithstanding a remarkable convergence in external features, is not 
identical with the Siberian types of Keyserlimjites {Ceratites subro- 
busti), their mode of development showing considerable differences. 
Since the Indian types of Keyserlingites cannot be allied phylogenetic- 
ally to the Siberian ones, they must be considered as a faunistic ele- 
ment peculiar to the Himalayan Muschelkalk. 
In America the fauna of the Muschelkalk in the West Humboldt 
range of Nevada, as studied by J. P. Smith,^ shows such a distinctly 
Mediterranean character, " that a palaeontologist from Austria might 
be set down in the Humboldt desert and he could hardly tell from the 
character of the fauna, whether he was collecting in Bosnia or in 
Nevada." 
Although the predominance of Alpine elements shows that the rela- 
tionship is much closer with the Mediterranean than with the Hima- 
layan Muschelkalk fauna, there is sufficient evidence for a direct connec- 
tion of the American Triassic province with the Indian regions during 
this epoch. 
The sub genus HoUandifes, which is of Indian origin, is represented in 
Nevada by two species nearly allied with Himalayan ones, H. aff. Void 
0pp. and H. aff. Hidimba Dien. The subgenus Gymnotoceras Hyatt 
(group of Ceratites geminati), which occurs abundantly in Nevada, is 
also represented in the Olenek beds of Siberia and in the Indian 
Muschelkalk, but not in the Alpine region. It seems therefore prob- 
able that at the Muschelkalk epoch the American Triassic province was 
connected on one side with the Mediterranean and on the other side 
1 Ueber die Entdeckung der Untertrias in Albanien, etc. Miiteil. Geol. Ges. 
Wien., I, p. 286, Taf. XH, fig. 4. 
2 J. P. Smith, The stratigraphy of the Western American Trias. Ad. v. Kanen 
festschrift, Schweizerbart, Stuttgart, 1907, p. 401. 
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