24 BRITISH MAMMALS 



of the Boston "Journal of Natural History it is stated by Professor 

 Wyman that during its captivity this beluga became quite tame, 

 and allowed himself to be harnessed to a floating car in which 

 a woman performer was seated. The beluga then swam round 

 the tank, dragging the little vessel with him. He recognised 

 his keeper, allowed himself to be handled, and at the proper 

 time would come and put his head out of the water to be 

 harnessed or to take food. This beluga was very playful in 

 disposition. He would take into his mouth a sturgeon and a 

 small shark which were confined in the same tank, and, after 

 playing with them awhile, allow them to go unharmed. He 

 would also pick up and toss stones about with his mouth. In 

 connection with this, it is rather interesting to note that sand 

 and pebbles are often found in the stomach of the beluga, as, 

 indeed, in some other whales. Two other specimens of the 

 beluga lived for a short time at the Westminster Aquarium in 

 1877 and 1878. 



Phocana communis. The Common Porpoise 



The Porpoises differ from the preceding genera in the larger 

 number of teeth which are found in each jaw, and which may 

 extend to as many as twenty-six on each side. The teeth are 

 peculiar in shape, being compressed, spatulate, and sometimes 

 divided into distinct lobes. The tooth is pinched into a narrow 

 neck between the crown and the roots. The porpoise differs 

 from the true dolphins in that it has a relatively round and 

 blunted head, the muzzle of which is not prolonged into a long 

 snout as in the dolphins. It is, like these other animals and 

 unlike the beluga, in the possession of a marked back fin. This 

 fin is remarkable in the porpoise for having often a row of 

 horny tubercles along its margin. These were first observed by 

 the English naturaHst, Dr. Gray, who in a specimen caught off 

 Margate noticed that these tubercles were calcified or bony. 

 This was a very interesting discovery. In allies of the porpoise 

 found in the Indian seas these calcified tubercles or scales tend 

 to spread along the whole back of the animal. Moreover, in the 



