SPECIES OF MAMMALS OF THE PACIFIC AEEA 135 



Fig. 54 — Common Dolphin 



The Long-beaked Dolphin (Steno) has a beak even longer 

 than the common dolphin and distinctly marked off from the 

 forehead. The teeth, twenty to twenty-seven in number, are 

 heavier than in the common dolphin and are roughened or fur- 

 rowed. The upperparts are blackish or deep gray, while the 

 underside is white. This slender species measures about eight 

 feet in length. The long-beaked dolphin is recorded from the 

 Malay Archipelago, but not elsewhere in the East Indies. 



The Slender Dolphins (Prodelphinus) are shaped like the 

 long-beaked dolphin but the teeth, which number thirty-nine 

 pairs in each jaw, are smooth. They differ from the common 

 dolphin (Delphinus) in having the palate flat, without the 

 deep grooves inside the toothrows found in that species. The 

 slender dolphin of the waters of the East Indies is ashy gray. 

 It is about six feet long. It may reach Japanese waters, but 

 the limits of its range are not known. 



The White Dolphins {Sot alia) of the Malay waters and 

 Chinese coast have long beaks ; the flippers are broad at the 

 base and have the posterior margin concave. The Malay species 

 is glossy white with gray dappling and has about thirty-seven 

 teeth in each row. The Chinese species may occur off Formosa. 

 It is milky white, with pinkish fins, and has thirty-two teeth on 

 each side above and below. A slaty-colored species, sometimes 

 called the lead-colored or plumbeous dolphin (S. plumbea), is 

 distinguished by its very long snout ; from the tip of the snout 



