1914] Toivnsend: The Porpoise in Captivity. 291 



turbed by high speed dashes for accurate observation. The ani- 

 mal undoubtedly relies upon its tail for propulsion, the flippers or 

 pectoral fins being brought into action in making turning move- 

 ments. Several of the porpoises have lately taken to swimming 

 on their backs, and the movements of the flippers and tail at 

 such times is easily seen as contrasted with the white under 

 parts. In swimming on the back, however, there is considerable 

 lateral action of the tail. 



Frequently three or four of them will bunch together in the 

 center of the pool, rolling and rubbing against each other in 

 a ball-like mass suggestive of the tussling of puppies. This 

 may at times mean that they are merely scratching, as the single 

 porpoise kept in the Aquarium for two and a half months last 

 summer frequently rubbed his sides or back against the back 

 of a large sturgeon kept in the same pool. This injured porpoise 

 indulged in no play and swam day and night in the same circle 

 from right to left, but always fed freely. 



There is considerable mobility of the neck of the porpoise, 

 an animal lacking all outward appearance of a neck. The head 

 can be turned down at an angle of about 45 degrees to the body, 

 and can be turned as far sideways with equal readiness. These 

 motions can be seen at feeding time and when the animals are 

 tossing fishes. 



There is no evidence that the porpoise can see out of water. 

 In throwing a fish the head is often thrust well above the sur- 

 face, but the animal seems to be always intent on its plaything, 

 entirely disregarding the visitors leaning over the rail five or 

 six feet away. While a fish thrown into the water is promptly 

 seized, the porpoise pays no attention to a fish suspended by a 

 thread two inches above the surface. If the eyes of porpoises 

 and other whales were fitted for observation above the surface 

 of the water, as are the eyes of seals, they might long ago have 

 learned to use them in the same way. 



Porpoises instantly recognize any change that may occur 

 in connection with the water level of the pool. The entirely 

 noiseless opening of a distant valve to lower the water, is appar- 

 ent to them and may stop their play temporarily. A pool only 

 thirty-seven feet in diameter does not of course afford space 

 for the high activity of which the porpoise is capable. Never- 



