5 1 4 JAMES PERRIN SMITH 



in the Himalayas and the Salt Range there was a continuity of 

 life and sedimentation from the Paleozoic into the Mesozoic, 

 and there the line of demarcation has been arbitrary. The 

 stages or zones used in drawing this paleontologic line in India 

 have become types, and are used in interregional correlation 

 wherever similar beds are known. A section is given below of 

 the uppermost Permian and the Lower Trias of India, for con- 

 venience of comparison with the American section. 



SECTION OF THE PERMIAN AND LOWER TRIAS OF INDIA AFTER WAAGEN, ClENER, 



AND NOETLING 



[ Middle — Upper Ceratite limestone. 



1 ^, 1 J ( Ceratite marls. 



I V. i.-4. J <. ( Flemingites beds. 



Trias \ ^ j Ceratite sandstone j gtachella beds. 



Per- 

 mian 



I \ r^^ u J ( Ceratite marls. 



Otoceras beds ^ T ^ ,., ,. , 



L 1^ ( Lower Ceratite limestone. 



( Upper Productus limestone, with Cyclolobus oldhami, and 

 Upper \ Xenaspis carbonaria. 



( Middle Productus limestone, with Xenaspis carbonaria. 

 J ( Lower Productus limestone, with Fusulina kattaensis. 



I Glacial beds. 



Waagen drew the line between Paleozoic and Mesozoic at 

 the base of the Ceratite formation because of a supposed uncon- 

 formity, and because the Permian types of brachiopods such as 

 Productus, Chonetes, and the Orthidae have not been found above 

 this line. But the unconformity has since been shown not to 

 exist, and several of the Permian ammonite genera range up into 

 the Ceratite formation, such as Otoceras, Medlicottia and Xenaspis. 



The upper Productus limestone is acknowledged to be younger 

 than any known European marine Permian, and the Otoceras 

 beds are universally considered to be older than any Trias yet 

 known from Europe; therefore the continuity of sedimentation 

 and life makes it exceedingly difficult to draw a line that will 

 satisfy everybody. And, indeed, if either the Trias or the Per- 

 mian had been named first in India, there would have been no 

 division of this series. 



The Wichita Permian of Texas, while carrying forms such as 

 Medlicottia, Waagenoceras, and Popanoceras, harbingers of the 

 varied Triassic ammonites of later times, contains in its other 

 members so many Paleozoic types that no one would think of 



