GEOLOGY. 35 



The fossil evidence to the contrary adduced in the foot note to page 

 512 of the Manual I look upon as inconclusive, for Mastodon latidens has 

 been collected by myself and identified by Mr. Lydekker from the rocks 

 near Kushalgarh as well as from the beds lithologically identical with 

 the Murree group near the Bakrala pass, east Salt Range. 



As to the unconformity upon a denuded surface of the nummulitic 

 rocks, I have followed the boundary between the latter and the succeeding 

 sandstones, &c, for some hundreds of miles over the Upper Punjab and 

 have never found an instance of either. I am therefore sceptical as to its 

 occurrence anywhere within that region. An unknown interval may 

 of course occur between the deposition of any two beds of rock however 

 parallel, but that this has taken place at the horizon indicated, accom- 

 panied by unconformity, I think the evidence available is insufficient to 

 prove. 



I have always stated that much irregularity of deposition over the 

 whole area has prevailed during the tertiary periods represented, and this 

 might occur even accompanied by strong evidence of overlap without 

 the presence of the decided unconformity which has been said to exist. 



12. Post-tertiary. — The unconformable limestone conglomerates that 

 cap the mountain over Kalabagh have evidently occupied their present 

 position so much before the full results of the denudation which fashioned 

 these mountains into their present form took place, that they may be 

 regarded as the oldest post-tertiary beds of the district. They are 

 formed of the harder local debris of the Salt Range series, and are pre- 

 sumably due to exceptional exertion of the denuding agency as the Indus 

 reduced its channel ; these conglomerates having been very probably old 

 valley beds of that stream. On the western side of the patch which 

 covers the hill of Kalabagh, the conglomerates are tilted and lie at 

 higher angles apparently than those of deposition. 



Among the newer post-tertiary deposits are included some part of the 

 coarse detrital fan and terraced accumulations of the district which have 

 been in process of formation ever since the recent denudation connected 

 with the present drainage system began to act. 



( 2i5 ) 



