THE PEEMO-TRIASSIC BOUNDARY. 
49 
LIII. p. 17), where a bed of limestone containing fossils of the Bellero- 
phonkalk is intercalated in shales lithologically identical with those of 
the Werfen beds. It is evident that in this section the highest beds of 
Permian age are developed in the facies of the Triassic Werfen shales and 
that the lithological boundary does not coincide with the true limit of 
the two systems. A development of Triassic limestones within the shales 
at the base of the Seis beds has been described recently by F. v. 
Kerner (Die Trias am Suedrande der Svilaja Planina, Verhnndl. K. K. 
Geol. Reichsanst., 1908, p. 26.3). 
The Permian age of the Otoceras beds was defended on this litholo- 
gical basis for a number of years against the counter-evidence of fossils. 
Noetling had indeed no palaeontological evidence in favour of the 
supposed homotaxis of the Himalayan Otoceras beds with the Chideru 
stage of the Salt Range. His only reasons for assigning a Permian 
age to the Otoceras stage, as deduced from a study of its fossils, are 
the following : — 
(1) the genus Otoceras is only known from Permian rocks ; 
(2) Episageceras Dalailamoe is a Permian species, so far as we can 
judge from the character of its suture-line. 
The fallacy in those two assumptions is so evident that it should 
not have deceived able geologists like Kayser (Lehrbuch der Geologie, 
11, Formationskunde, 3. Aufl. 1908, p. 301) or Steinmann {Einfuehrung 
in die Paloeontologie, 2. Aufl. 1907, p. 326). 
It is true that the genus Otoceras is known outside the Himalayas 
from Permian rocks only, a small number of species, represented by a 
few fragmentary examples, having been collected from a single locality 
(Julfa on the frontier of Persia and Russian Armenia). But there is 
not a single case of specific identity with Himalayan forms. The 
Armenian species of Otoceras are associated with a rich fauna of dis- 
tinctly Palaeozoic aspect. The numerous types of Productidce, OrtJiidoe, 
Spiriferidoe, Gastrioeeras , differ so widely from anything that is seen in 
the fauna of the Indian Otoceras beds, that the presence of the genus 
Otoceras at Julfa does not justify the assumption of its being restricted 
to the Permian. Hungarites, the nearest ally of Otoceras, is certainly a 
Triassic genus, although it makes its first appearance in the Otoceras 
beds of Julfa. Xenodiscus also ranges from the true Permian into the 
upper division of the Lower Trias. The species of Otoceras, which have 
E ( 250 ) 
