MALLET, VINDHYAN SERIES. 45 



that even these were representative. The general litholog-y is, however, 

 striking-ly similar. For instance, the shales. No. 10, are identical in 

 appearance with the Pulkoas, Both in their natural state are hlack, very- 

 hard, and cut up into little cubes by jointing, and become white and par- 

 tially disintegrated by weathering. Very much the same as this are the 

 black shales of Bui'dhee and of the Boghin valley* which, it may be 

 remarked, have both been mistaken for coal, and attempts made to work 

 them. The general aspect of limestone, sandstone and shales is the 

 same in both, being distinguished by a thin-bedded, flaggy structure, and 

 frequent rippling, and the tendency of the members to graduate into 

 each other. Certain varieties of rock, however, seem confined to one dis- 

 trict. Such are the Tirhowan breccia, and the trappoid beds, so far as we 

 know. 



Except one or two doubtful cases of local breaks, to which allusion 



has been made when speaking of the bottom sand- 

 Boundaries. 



stone, the southern boundary of the lower Vind- 



hyans is a natural one throughout from Botasgurh to the Mahanuddy. 



West of this stream the junction iFmarked by the commencement of a 



great fault, to be described hereafter, which extends a long way down the 



Nerbudda valley. Outhers, sometimes of large size, are not unfrequently 



found scattered over the slate area to the south, these being, it appears, 



always made up of the bottom sandstone alone, which there attains a 



greater thickness than anywhere in the main area .The outliers generally 



assume the form of narrow longitudinal ridges, parallel with the strike, 



and are distinguishable by theu' contour from hills of older rock. Inliers 



are very uncommon and of small importance. One such at Sulkhun, 



north-east of Agoree Khas, owes its existence to a small anticlinal, by 



which the lower beds are brought up. At the bend of the Mahanuddy, 



at Koteesar, there is another case where a low hill of most peculiar 



* Memoirs, Geol. Surv,, India, Vol. II, p. 92, 



( 45 ) 



