NIIMMULITIC FORMATION. • 13 



whether the Gieumal sandstone or any part of it corresponds to the. 

 fossiliferous zone^ is, on the evidence before us, impossible to decide. 



The unfossiliferous limestone group presents all the appearance of 

 passing upwards into the nummulitic formation, and may have a thick- 

 ness of from 50 to 70 feet. 



6. The Nummulitic formation, as usual among the border hills of 

 the Punjab, is chiefly composed of massive gray and blackish limestone, 

 here alternating, less than it generally does, with thick zones of dark 

 colom-ed shale. Its thickness is very great, its stratification violently 

 contorted, and it possesses the same features commonly observable, of pro- 

 found gorges and ravines excavated in it, high cliffs formed, and, upon 

 slopes, of great masses having subsided so as to produce complications 

 of slippage often exceeding in amount the throw of genuine faults. 



Its fossils are not well preserved, and with some exceptions the beds 

 appear to be pervaded by swarms of small NummicUna and other 

 Toraminifera, casts of gastropods and other shells, more or less imper- 

 fect ; occurring here and there as well. In one or two places a few beds 

 of soft white sandstone form its base. 



With a view to clearer illustration of the structure of the mountain, 

 the following rough sketch sections (not drawn to scale) are extracted 

 from our note books ; — 





( 343 ) 



