996 NATURAL HISTORY. 



exclusively from sharks, but also from rays, and assorted in two kinds ; viz. 

 ' white and black.' The white consists exclusively of the dorsal fins, which 

 are on both sides of the same uniform light color, and reputed to yield 

 more gelatine than the other fins." Kurachee, on the west coast of India, 



Fig. 2 l Jl. — Common dog-fish (Squalus ucanthias), above; sea-hound (Mustehts cunis), below. 



is the great seat of the shark-fishing industry, and the annual catch amounts 

 to some forty thousand. 



The skin of sharks is covered with small hard scales, each of which is 

 spined. This makes the surface very rough, and the skin when taken off 

 and dried figures in trade as shagreen, and formerly had an extensive use 

 by carpenters and cabinet-makers in smoothing their work; but to-day 

 sandpaper has driven it entirely out of the market, on account of its greater 

 cheapness. 



