WATERS OF WESTERN INDIA. 155 



sea -level there is no change in their population ; but here we find 

 a tiny prawn associated with the loaches and Discognathus modestus ; 

 and below this we come upon Discognatlius lamia and a number of 

 small Barbel and Carps, mostly, I suppose, fry of large species. Near 

 the same level we begin to get a small Murrel ; and at the next step 

 downwards the torrents unite to. form small rivers, flowing through 

 valleys of which the bottoms are usually under rice-cultivation. 



These rivers very much resemble thoss of the Western Deccan 

 described in my last paper ; but. before they have time or space to 

 unite and form important channels, they meet with the salt water. 

 Probably no river of the Konkan has a perennial fresh- water stream 

 fifty miles long. 



There are however many deep potholes under falls ; and in some 

 places long reaches of still water are formed by natural trap dykes 

 crossing the streams or by artificial dams. 



Some of the valleys are mere gorges ; others are of considerable 

 width ; and these latter have usually flat bottoms, and appear to 

 have been lakes within (geologically) recent times. Many of my 

 readers are probably familiar with the theory that the basaltic floor of 

 the Konkan, or at least of that part of it near Bombay, did, within 

 the present period, sink westwards, somewhat as ice sinks from the 

 shore when the water fails under it, immersing its western edge in 

 the sea, and forming, amongst other things, Bombay Harbour, where 

 there had probably been a lake surrounded by forest. In digging the 

 Prince's Dock, a forest of Kheir trees ( Acacia catechu) was found m 

 situ, very much as you may see to-day the same trees growing in 

 the forests of Mosare and Kirawli, five and twenty miles away; aud 

 recent excavations in the salt marshes of Uran showed numerous 

 roots and twigs with the bark on them : these however were not 

 identified, and may have been mangroves ; but even this implies 

 a depression of their bed, as mangroves do not grow below low-water 

 mark. 



The lacustrine remains found in the Island of Bombay itself may 

 perhaps belong to another period. I am not personally acquainted 

 with them. 



But the recent depression that let the sea into Bombay Harbour 

 would naturally spill the fresh water out of lakes lying further east, 

 such, for instance, as the wide Panwell Basin, over which people look 

 towards Bombay from the west edge of Matheran, or from the 

 reversing station on the Bhor Ghat. The same thing probably 



