KHASI HILLS. " 119 



These beds containing the echini (Gyrtoma of McClelland) form a 

 well-marked line along the face of the Cherra valley, where the beds are 

 calcareous, and are again well seen under Mawmluh, where they were 

 first noticed by Dr. McClelland (a). Associated with these echinoderm 

 remains, and occurring also a little below them, are large plicated 

 oysters, generally in fragments. 



Over this group are numerous beds of soft earthy sandstones, of 



brownish and red tints, with intercalated beds of 

 Plant remains. 



clay and thin shales. These continue with little 



intermission until the flat of Cherra Poonjee is reached, where thick- 

 bedded strong sandstones occur, not very hard, and of a reddish colour. 

 In these beds I have not observed any remains of shells, but impressions 

 of stems of large plants, very rudely preserved and in most cases much 

 too indistinct for identification, are not uncommon. 



Over these sandstones, and separated apparently by a thin bed of 



stiff blue clayey shale, comes the limestone which 

 Limestone. 



forms the bluffs of the small detached rido-e in 



o 



which the coal has been worked to the West of the station of Cherra 

 Poonjee. This limestone is here about 80 feet thick, separated above 

 by eight to ten feet of sandstone and shale from the coal, which again 

 is covered by alternating beds of soft grits and clays to the top of the 

 HUl (see below). 



The thickness of the entire group, which I have just described, is, 

 „, . , ^ near to Cherra Poonjee, not less than 2,000 feet. 



Thickness of tertiary •' 



S'^o'^P- Throughout the whole of this great thickness the 



beds are entirely conformable, and are very nearly horizontal in position. 

 They are irregularly developed, beds of sandstone and clays often 



(o) These beds of sandstone, which, beiiis soft and loosely coherent, are readily acted 

 upon, and decompose into a friable sand in which the harder portions of the organic re- 

 mains continue imbedded, gave rise to the idea, which Dr. McClelland has published, of 

 their forming a sea-beach. The true relations of the beds, or so-called " beach," can be well 

 seen in the adjoining cliifs, where the conformable association of these beds with the other 

 sandstones may be traced. 



