540 J. G. Malcolmson, Esq., on the Fossils of 



form of the Mysore. It is on the banks of the Kistnah that the richest dia- 

 mond mines occur, and that the sandstones acquire their greatest elevation, 

 amounting to more than 3000 feet ; the river passing through mural preci- 

 pices of this rock and of the schistose limestones to be presently described. 

 It then enters the plains of the Carnatic, where the same rocks occur, some- 

 times a little elevated above the level of the sea, at others forming the caps of 

 granite mountains, or broken up by varieties of greenstone and basalt. Thence, 

 passing through a narrow gorge in the gneiss hills of Bezwarrah, it enters the 

 alluvial plains continuous with the delta of the Godavery. Its waters, how- 

 ever, are more loaded with mud than the last-mentioned beautiful river, and 

 the deposit of new land may be seen, by the inspection of a common map, to 

 be proportionably great. 



The Pennar is comparatively a small stream, but of much geological inter- 

 est, the greater part of its waters being derived from the districts in which 

 the diamond sandstones and the argillaceous limestones, on which they rest, 

 are exhibited in their most characteristic forms, and where they are most easily 

 investigated. To describe these strata in detail would be out of place here ; 

 but a few of the leading facts must be stated, that the identity of the forma- 

 tions with those of the fossiliferous district, more immediately the object of 

 this paper, may be rendered manifest. Like all the rivers of Southern India, 

 granite is frequently seen in the bed of the Pennar, more especially in its 

 southern branches, where the passes of Ryachottee lead to the granitic table 

 land of Mysore, having an elevation of 3000 feet above the sea, or 2500 above 

 Cuddapah, the principal town of the Pennar basin. With these exceptions, 

 and the occasional appearance of trap through the stratified rocks, the rest of 

 its course, till it approaches the sea, is over rich plains of black and saline 

 alluvium, derived from the decomposition of basalt and of the stratified rocks 

 so often referred to. From these plains numerous table lands, insulated emi- 

 nences, and ranges of hills, having for the most part a direction nearly N.E. 

 and S.W.,rise abruptly, presenting mural precipices of difficult access, around 

 the base of which the roads often make extensive circuits. The Nulla Mulla 

 hills extending from the Mysore frontier to the basins of the Kistnah and 

 Godavery, and the minor ranges dependent on them, and having the same 

 composition and direction, are crossed at right angles by the Pennar, which 

 makes its way through them, like the Kistnah, by traversing narrow gorges 

 with perpendicular sides. 



There is not a more remarkable phenomenon in the district watered by the 

 Pennar than the horizontal summits of many of the ranges, and the distinct 

 manner in which the continuity of the strata can be traced from one hill to 



