34 BLANFORD : GEOLOGY OF WESTERN SlNl). 



The sandstones resting on the hippnritic limestone occupy a consider- 

 able tract around Barrah hill, and extend for about 

 3 miles from north to south. They are also 

 seen at Jakhmari, about 5 miles south of Laki to the northward, and 

 in one or two other places in the neighbourhood. They are gritty and 

 conglomeratic, frequently calcareous, and they include a few bands of shale, 

 usually of a red colour. The prevailing tint on the weathered surfaces 

 is dark-brown or purple, many of the beds being highly ferruginous. On 

 the top of the sandstones is a thick bed of dark-coloured impure limestone, 

 containing oyster-shells, and occasionally large bones, apparently of 

 reptiles ; none, however, have been found sufficiently well preserved for 

 identification. 



In one place a bed of basalt, about 40 feet thick, has been found 



interstratified in the sandstones, and. it is possible 

 Interstratified basalt. .,,,111 • , -i 1 mi -±i 



that the band may exist elsewhere, the position 



of this bed of basalt on the face of a hill called Bor, a little south of 



Barrah, and about 13 miles north of Ranikot, is at an elevation of 300 or 



400 feet above the base of the sandstones, and about twice as much 



beneath the main band of interbedded trap, to be described presently. 



The highest sub-division of the cretaceous formation consists of soft 



olive shales and sandstones, usually of fine texture. 

 Cardita beaumontihe&s. ,11 



The sandstone beds are thin, and frequently have 



the appearance of containing grains of decomposed basalt or some similar 

 volcanic rock, or else fine volcanic ash. A few hard bands occur, and 

 occasionally, but rarely, thin layers of dark-olive or drab impure lime- 

 stone. Gypsum is of common occurrence in the shales. 



The olive shales are highly fossiliferous, the commonest fossil being 



Cardita beaumonti 1 , a peculiar, very globose species, 

 Palaeontology. . , 



truncated posteriorly, and most nearly allied to 



forms found in the lower and middle cretaceous beds of Europe (neocomian 



and gault) . This shell is extremely abundant in one bed, about 200 to 



250 feet below the top of the cretaceous series, but is not confined to 



1 IVArcliiac and Hainie, An. foss. Groupe Num. de l'lnde, p. 253, pi. xxi, fig. 14. 



( 34 ) 



