OCEANIC MAMMALS 479 



Family INIIDAE: Fresh-water Dolphins 

 WHITE-FLAG DOLPHIN; YANGTSE DOLPHIN 

 LIPOTES VEXILLIFER Miller 



Lipotes vexillifer Miller, Smithsonian Misc. Coll., vol. 68, no. 9, p. 8, Mar. 30, 1918 



(Tung Ting Lake, Hunan Province, China). 

 FIGS.: Miller, 1918b, pis. 1, 2, 4, 6, 8, 9, 11, 12 (exterior and skeleton). 



This remarkable fresh-water dolphin was discovered as re- 

 cently as in 1916, when Charles M. Hoy, for some years a 

 resident in China, secured a specimen and sent it to the U. S. 

 National Museum, where it was studied and described two 

 years later by Miller. The species is known only from the 

 large fresh-water lake of Tung Ting, in the interior of southern 

 China, and may be regarded as a relict of a group of dolphins 

 once more widely spread, with its nearest living relative Inia 

 geoffrensis, of the Amazon River. 



About 2.5 meters in length, this is a long-beaked dolphin, 

 with a low triangular adipose fin on the back. The color is 

 "pale blue-gray above, white below." The "beak" has a 

 slight upward curve, whereas that of Inia is the reverse. There 

 is a long mandibular symphysifc, and each tooth row carries 31- 

 33 teeth. The eyes are very small. The teeth have "the form 

 of the crown and character of the enamel-wrinkling much as in 

 the median teeth of Inia, but root not thickened, the entire 

 tooth resembling that of the Miocene 'Schizodelphis'." Basal 

 length of skull, 510 mm.; rostrum 350. Weight, 297 pounds. 



Hoy (quoted by Miller, 1918b) writes that the local name 

 Pei Ch'i given to this dolphin by the Chinese means "white 

 flag" because of the dorsal fin, which they liken to a flag; it is 

 prominent when the animal comes to the surface to breathe. 

 "The sudden appearance of a school of these whitish dolphins 

 close to a small boat is very startling. To the best of my knowl- 

 edge this animal is found in large numbers only around the 

 mouth of Tung Ting Lake. In winter when the water of the 

 lake is so low that there is scarcely more than the river channel 

 left they are easily seen and are found in great numbers in 

 bunches usually of three or four, but occasionally of as many 

 as 10 or 12 individuals. They are often seen in shallow water 

 working up the mud in their search for fish. The one I killed 

 had about two quarts of catfish in its stomach. When shot it 

 gave a cry like that of a water-buffalo calf. In summer the 



