480 EXTINCT AND VANISHING MAMMALS 



water rises to a height of 48 feet above its winter level. The 

 mountain streams feeding the lake are then full, and the dol- 

 phins disappear. The natives say that in the late spring when 

 the lake is rising the dolphins make their way up the small, 

 clear rivers, and that these are their breeding grounds. " Be- 

 yond the fact that the British Museum and the American 

 Museum of Natural History have each since acquired a speci- 

 men, and that there are a skull and a jaw in the Shanghai 

 Museum (without data), nothing further seems to have been 

 ascertained concerning this remarkable animal. Hoy's speci- 

 men weighed about 297 pounds. The Chinese usually regard 

 this dolphin with a certain superstitious fear and seldom kill it, 

 but as its blubber is thought to be of medicinal value, it is not 

 impossible that in the future increasing numbers may be shot 

 as improved weapons reach these parts of China, or the demand 

 for specimens offers an inducement to hunters. As a sort of 

 "living fossil," a relict from earlier ages, and the only strictly 

 fresh-water dolphin in eastern Asia, the species is worth pre- 

 serving. 



Family DELPHINIDAE: Dolphins and Porpoises 

 FALSE KILLER WHALE 



PSEUDORCA CRASSIDENS (Owen) 



Pkocaena crassidens Owen, Hist. British Fossil Mammals and Birds, p. 516, 1846 

 ("In the great fen of Lincolnshire . . ." near Stamford, England). 



FIGS.: True, 1889b, pi. 44 (exterior and skull); London Illustr. News, Dec. 21, 1935, 

 p. 1125. 



While apparently not threatened or vanishing, this large 

 porpoise may be included here as an example of a species that 

 was believed to be extinct but that later proved to be living 

 and in considerable numbers. It was first described in 1846 

 from a skull found in the great fen of Lincolnshire, England, 

 but in 1862 Reinhardt gave an account of it from three indi- 

 viduals that were thrown ashore on the Danish islands Sealand 

 and Funen, in that year. Since then but few specimens have 

 been made known, until within a few years a number of schools 

 have been reported as stranded in various parts of the world. 



This porpoise attains a length of up to 20 feet. It is black 

 all over, with a large bulbous snout, which slightly overhangs 

 the mouth. There is a good-sized falcate fin on the lower 



