46 C. Schucliert — Russian Carboniferous and Permian. 



existence of the Otoceras beds or their equivalents in this part 

 of the Trias sea. 



" I had serious doubts about this conclusion, for on my visit 

 to Chideru in the Salt Range I was convinced that there is 

 here a gradual transition from the Upper Productus-limestone 

 (Permian) to the Ceratites beds (Trias). 



" This observation is not new, for at different times Wynne 

 has pointed out the gradual passage in the sequence of the 

 beds from the Productus-limestone to the Ceratites beds, but 

 his statements have unfortunately received too little attention " 

 (p. 529). 



On this visit Noetling looked for the Otoceras beds at the 

 base of the Ceratites zone below the Ceratites-limestone, but 

 did not find this diagnostic fossil. To his great surprise he 

 did find what he took to be an Otoceras in the Ceratites- 

 shale, i. e., above the Ceratites-limestone. On his return to 

 the museum at Calcutta, however, the fossil proved not to 

 belong to this genus. After a further dissection of the Him- 

 alaya section he states : " In the Himalaya the Otoceras beds lie 

 immediately below the Hedenstroemia beds. Accordingly, in 

 the Salt Range, either the Otoceras beds or their equivalents 

 must be looked for immediately beneath the Ceratites beds. 

 As, however, in the Salt Range, immediately beneath these 

 beds lies the Permian (Upper Productus-limestone = Chideru 

 group) it follows that we have to seek for the equivalents of 

 the Otoceras beds in the Salt Range in the Upper Productus- 

 limestone, probably in my Euphemus indicus zone, but over 

 the zone with Episageceras wynneiP In spite of careful col- 

 lecting none were found, and he concludes : " According to 

 our experience we almost doubt the occurrence of Otoceras in 

 the region of the Salt Range." The two regions have a differ- 

 ent stratigraphic sequence with somewhat different faunas, and 

 it may be that they were separated from one another by a sub- 

 merged barrier (a rising anticline) not wholly preventive of 

 intermigration. 



Then follows a long discussion 01 the apparently complete 

 transition zone in the Himalaya, between the Productus-lime- 

 stone and the Ceratites beds, and considerable detail regarding 

 the included fauna as well. This discussion is entirely too 

 long and too detailed to be summarized here, but JSToetling's 

 views are clearly presented in two correlation tables, one of 

 which has been added to the table given on Plate I. 



[To be continued.] 



