CRETACEOUS. T 79 



The section in the nala-bed becomes obscured, above this, by 

 recent debris and boulders of soft sandstone. The next exposure is 

 that of the massive gneiss on the hill-top. 



A fairly good section is seen near Silbatta, a small trading 



station, consisting of one grass hut, at the 

 Silbatta. 



Jamuna Falls. 



At the foot of the Falls, and again about a quarter of a mile above 

 them, the gneiss is seen to be overlaid by a band of decomposed 

 and hydrated earthy trap. The trap presents a mottled appearance, 

 dark-red and dull-green in colour, and seems to be some 20 feet in 

 thickness. 



It is overlaid by a bed of white argillaceous rock, very like chalk 

 in appearance, but neither calcareous nor fossiliferous. The white 

 rock is slightly nodular below, but stratified above, with a dip of 

 5 S.E. It has about the same thickness as the mottled trap. 



Above the argillaceous rock the section is obscured, both above 

 and below the Falls ; but the next exposure in both cases is of 

 nummulitic limestone dipping gently north to north-west. 



Beds of decomposed trap are seen overlying the gneiss in several 

 of the river-beds, where sections are exposed. 



Other localities. 



In the Jamuna river, north of Miji, two bands 

 of hydrated trap cross the river-bed, apparently resting on the 

 gneiss. The trap is of a light blue-green colour when freshly 

 broken, with brilliant grey grains scattered through it, very like gra- 

 phite, but it usually changes into the dull coloured mottled trap 

 near the surface. 



I attempted to cut sections of several of these trap bands, but the 

 rock was too rotten to hold together. The grey grains, however, 

 turned out to be a titaniferous iron-ore. 



On the Haria Jan a band of dull-green trap is seen resting directly 

 on gneiss, and underlying the nummulitic rocks, but no contact- 

 section with the latter is visible. 



A similar band is seen on the north bank of the Deopani, where 



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