Chap. 12.] w. blanpord, western india. 67 



The thickness of these deposits varies greatly, and it is difficult to 



estimate it. Sections of upwards of 50 feet in 

 Thickness. 



heig-ht are occasionally seen on the river banks, 



more frequently, however, 20 to 30 feet are exposed. In some cases the 



whole of this thickness consists of g-ravels and sands. More commonly the 



greater portion is clay, the coarser beds only being seen towards the base. 



Fossil bones in the lower Nerbudda and in the Taptee valleys are 



by no means abundant, and only a few fragments 

 Fossils. 



have been met with here and there. It is probable 



that closer search will result in additional discoveries, but many hours 



have been fruitlessly spent in examining the banks of the different rivers, 



the Taptee especially. Shells are common, and they appear in every case 



to have been of species [a] now met with in the rivers. 



In one portion of the Berar alluvial plain there is a considerable 

 ■ s It ' 11 * m of qi^antity of common salt in tTie clay, so much 

 ^^^'^T^' around Dhyunda and other places, north and north- 



east of Akola, that wells are sunk for the purpose of obtaining brine for 

 manufacture, and much salt is made. This does not appear to be the case 

 elsewhere. The salt-bearing stratum appears to be very low down in 

 the alluvium, the wells which are dug into it being of great depth. It is 

 beneath the gravels, and may, not improbably, be something distinct from 

 the upper fresh water alluvium, and of greater geological age. The pre- 

 sence of common salt in large quantities may also indicate that the clays 

 containing it are of marine origin {b) . 



It is evident that these extensive alluvial plains have not been formed 



. bv the rivers which traverse them under pre- 



Present streams do not •' 

 deposit. cisely their present conditions. These streams are 



now, in fact, wearing away the clays and gr avels; they have cut deep 



(a). Closer comparison than has hitherto heen made is, however, desirahle. In some cases, 

 where there is no specific distinction, there may be slight differences worthy of note amongst 

 shells so variahle as species of Unio and Melania. 



(b). I had not myself an opportunity of examining the salt-producing area of the Poorna 

 valley. Mr, Wynne, who surveyed the country, noticed no peculiarity in the alluvial clays. 



( 229 ) 



