xu PLATANISTA AND INIA 381 
The following are its main characters :—Dorsal fin absent. Eyes 
rudimentary. Pectoral fins large and truncated at the extremity. 
Teeth, about twenty-nine in each half of each jaw. Scapula with 
the acromion coinciding with its anterior edge. Skullwith enormous 
maxillary crests,and with the palatines entirely concealed by the 
pterygoids. The length of the above definition will serve to 
indicate how anomalous in many particulars is the structure of 
this “ Dolphin.” 
There is apparently but one species, P. gangetica, the “Susu.” 
The Indian vernacular name is derived from the sound that the 
animal makes when spouting. It is an inhabitant of the Ganges 
and the Indus, together with their tributaries, and ascends very 
high up its streams. It is also thought to be purely fluviatile 
and never to desert the rivers for the sea. Platanista lives 
chiefly by grubbing in the mud for prawns and fish. Grains 
of rice have also been found in the stomach, but this would seem 
to be accidental. The long snout of the Susu has been compared 
to the long snout of the Gharial, a native of the same region. 
This Whale grows to a length of over 9 feet, but this length is 
exceptional. Its anatomy has been elaborately described by Dr. 
Anderson.' 
The next genus, Znia, is thus to be characterised :—Dorsal fin 
rudimentary ; pectorals large and ovate. Teeth, as many as thirty- 
two on each side, often with an additional tuberele. Skull without 
large maxillary crests; palatines not hidden by pterygoids, but 
divided by vomer. The vertebrae of this genus are few in 
number, only forty-one in all, which are thus distributed: C 7, 
D'13,L 3, Ca 18. The peculiarities of the vertebral column 
are several. In the first place, as has been mentioned in the 
definition of the family, all the cervicals are separate and 
individually of some length. Secondly, the axis has a better 
trace of an odontoid process than in any other Whale except 
Platanista, where it is even more obvious. The lumbar region is 
remarkable on account of its restriction to three vertebrae. The 
sternum, by what we must regard as convergence, is somewhat 
like that of the Whalebone whales. It consists of one piece only, 
of a roughly-oval form, to which apparently only two pairs of 
(cartilaginous) sternal ribs are attached. In the fore-limb the 
proportions between the humerus and the radius are more like 
1 Anatomical Researches Yunnan Exp. 1878, p. 417. 
