66 FOLLOW THE WHALE 



is of the length of i6 cubits." Apart from a quadruplication of the 

 size, this is undoubtedly a description of the Susu, the animal to 

 which we now apply the scientific name of Platanista gangetica. 



This is perhaps the most curious and specialized of all the whales. 

 It lives in the muddy waters of the Indus, Ganges, Irrawaddy, and 

 Brahmaputra rivers and ranges from the tidal estuaries to the foot- 

 hills and up all the tributaries of those rivers as far inland as there is 

 water and no rock barrier in the stream. It appears to migrate up and 

 down the rivers to some extent, going farther inland in the hot sea- 

 son. It feeds on fish, prawns, and shellfish for which it grubs about 

 in the mud at the bottom. It can stay under for two minutes but 

 usually rises regularly and quietly at short intervals to breathe. At 

 other times it may become very active and leap clear of the water. 

 The name "susu" is in imitation of the noise it makes when breaching 

 to effect its extremely quick exhalation and inhalation of air. 



Susus grow to a length of about nine feet, but one caught in the 

 Jumna River was twelve feet long. They are entirely black, rather 

 elongated little whales with a distinct neck, so that the head is 

 movable. In place of a dorsal fin they have a slight elevation just 

 behind the middle of the back, and the flippers, instead of being 

 tapered like those of almost all other whales, are triangular, narrow 

 at the base, and cut off square at the end. The head is round and 

 swollen in front, due to two large, bony crests on the skull, but is 

 prolonged into a great bill rather like that of the gharial crocodile, 

 which inhabits the same rivers. This beak, or bill, is laterally com- 

 pressed, half as long again in the female as in the male, slightly ex- 

 panded at the tip, and armed with some 120 teeth. These are long, 

 pointed, recurved, and so close together they almost touch at the 

 base in front, but become gradually smaller, more widely separated, 

 and more laterally compressed as they approach the back of the jaws. 

 As the animal advances in age these teeth become worn down until 

 they are just flat-topped, cylindrical pegs. The whole mouth struc- 

 ture is very singular and is devised for probing in the mud and for 

 grabbing the quick things found there. 



The susu has other oddities. The eyes are minute and rudimentary, 

 the whole eyeball being no bigger than a pea; there is no lens and 

 the optic nerve is reduced to a thread. The external opening of the 

 ear is about the size of a pinhole. The blowhole, unlike that of any 



