TRIASSIC. 97 



sandstone beds with spinose Ceratites, marls, limestones, and sandstones, 

 form the upper portion of the group, and contain, besides Ceratites, 

 numerous specimens of Qervillia, a Cardinia, Rhi/nchonella, dnoplophora, 

 OrtJioceras, &c., being generally characterised by a predominance of 

 bivalves.^ 



The succession varies frequently as to details, and some of the 



limestones are magnesian, or dolomite bands take 

 Magnesian. t • i • i 



their place. Sometimes layers of glauconitic 



limestone (or pisolitic limestone with glauconite) occur, and beds of 



conglomerate, in one instance formed of huge limestone blocks, are 



sometimes present. 



This representative of the Trias first appears in the neighbourhood of 



Kurat and Katwahi, and extends thence to the 

 First appearance. 



westward, except where interrupted by dislocation. 



It also occasionally occurs in isolated or surrounding outliers as near 



Virgal. It is well seen near Chideru, and from the vicinity of Sakesar 



accompanies the carboniferous formation everywhere to its disappearance 



at Khyrabad. 



The group is characterised throughout by the number of Ceratites 



which it contains. Certain species of these prevail 

 Ceratites. 



m certain zones, and one band is marked by a pre- 

 dominance of the genus BellerophonX — an instance of geological history 

 repeating itself, the same genus occupying, as has been said, a strongly 

 marked zone in the upper part of the foregoing group. 



^hese triassic rocks, though lithologieally distinguishable, present no 



No strong lithological ^"^^ marked contrast to the carboniferous form- 



contrast. ation as exists between the Trias and succeeding 



beds. The limestones are more thin-bedded, and the shales or marls of 



* This information as to fossils is given from Dr. Waagen's notes, 

 f This name must be distinguished from Khewra. It is exactly represented by the old 

 spelling " Koora." 

 X Dr. Waageu, 



N ( 97 ) 



