lis KHASI HILLS. 



raerates. The pebbles are chiefly of quartz, both crj'stalline and grar 

 uular, all considerably rounded, and of all sizes, from six inches diameter 

 to one inch. Masses double this size are found, but are not common. 

 These are imbedded in a felspathic gritty cement. This conglomerate 

 is well seen in the Cherra valley ; and in places it is fully seventy feet 

 thick, forming a very well marked line of cliff along the sides of the 

 glen. On this coarse conglomerate rests a sharp semi-angular grit of 

 a dark brownish colour varied by numerous light specks. These are 

 scarcely-rounded fragments of felspar crystals, of a light flesh-red colour, 

 which give the rock a very peculiar aspect. Locally, these beds become 

 coarser and pass into a pebbly grit, and in this case, it can occasionally 

 be seen that these imbedded pebbles are partly of granite, and not 

 altogether of felspar (a). With local variation in texture and coarseness, 

 these beds are at least 150 to 200 feet thick. 



Over these come sharp grits of reddish -brown and greyish-brown co- 

 lours, in which are many casts of shells, generally 



Fossiliferoua beds. . ,. piir-i 



imperfect and fragmentary (cardium, &c.) Higher 

 up, the sandstones have a greenish-brown tint, and contain numerous 

 remains of echinodermata. These beds become calcareous, and then 

 decompose into a brownish-red sandy rock, which on the fresh fracture 

 is a very hard mass of a bluish tint. Where the fossils occur in 

 the grits, they are only casts, or the place of the original shell is 

 filled with a soft yellow impalpable clay ; where the rock is 

 calcareous, the shells of the echini are replaced by carbonate of lime. 

 It is almost impossible, owing to the nature of the matrix, and 

 to the highly crystalline condition of the carbonate of lime, to obtain 

 good specimens of these. At the base of the fossiliferous beds there 

 are locally developed some beds of a nodular dark grey shaly sandstone 

 (Mahadeo). 



(a) These beds are well seen at the zig-zags, on the road to Teria-ghat from Cherra 

 Poonjee, o£ which they form a sonsiderable portion. 



