140 BLANFORD : GEOLOGY OF WESTERN SlND, 



collectively, is found employed for any portion of a range by the people 

 of the country. About the Hala-lak, on the western side, the calcareous 

 rubbly Gaj beds are seen resting on the surface of the Khirthars, the 

 latter being worn and riddled with holes made by boring mollusca. 

 The Khirthar surface, forming the floor on which the Gaj beds have 

 been deposited, is in places of marly limestone, in others of fine calcare- 

 ous yellowish sandstone with casts of Enmmulites leymeriei. These 

 upper Khirthar beds are of a light buff colour, and contrast with the 

 more purely white limestones of Eri Hill and the range generally. 

 Amongst them is a bed containing fossil crabs {Arges, or Galenopsis 

 omtrchisoni) in abundance. Cerithium giganteum, Ovulum, and casts of 

 Lamellibranchiata also occur. 



Some miles farther south, the range is traversed by the Baran river, 

 and a very fair section of Khirthar beds is exposed in the gorge, which 

 is known as Darwaz or Darwat. In the cliffs on each side of the river 

 the massive Khirthar limestones are seen, dipping at a low angle to the 

 westward, except at the east end of the pass, where they are suddenly 

 bent down at a high angle and dip east. Fossils are of frequent occur- 

 rence in the limestone, but are chiefly common species ; the crab bed is 

 well seen north of the stream on the western side of the pass. 



The range south of the Baran river and east of Bhule Khan's 



Thana is known as Surjano, and here the upper 

 Surjano range. 



portion of the Khirthar group, composed of rubbly 



and rather shaly beds, not compact, is much thicker than farther north. 

 The commonest nummulites in these beds are N. granulosa, N. ley- 

 meriei, and N. spira, some layers being entirely composed of these 

 species. Some of the beds are yellowish in colour. A band of green- 

 ish clay, or fuller's earth, is found interstratified with these upper beds, 

 and is occasionally dug out by the natives and used for washing 

 cloth, &c. 



The upper shaly portion of the group is from 300 to 500 feet thick 

 near the Darwat ; below the shaly beds comes the whitish compact 

 limestone forming the mass of the range. Farther to the southward, 

 ( 140 ) 



