DOLPHINS 273 



genus is to be distinguished from Sotalia by the 

 rugose crowns of the teeth, which are smooth in 

 Sotalia, and by the closely approximated pterygoids. 



Steno rostratus, of Desmarest,* is in colour purplish 

 sooty black above, sides with yellowish white spots 

 under surface white, tinged with rose. Teeth, 20-27. 

 The ribs are 13. Vertebrae, 65. 



This species, if all the synonyms (Delphinus 

 frontatus^ Cuvier ; D. bredanensis, Cuvier ; D. 

 planiceps, Schlegel ; Steno compressus, Gray ; D. 

 reinwardti, Schlegel ; D. Pernettyi, Desmarest) 

 rightly apply to one species, ranges from the 

 Atlantic to the Indian Ocean. It is a largish 

 dolphin, measuring eight or nine feet. 



The remaining species, Steno per spicillatus, Peters, f 

 may be thus defined : Colour, black above, white 

 below, sides yellowish white ; a black line from ring 

 round eye joins its fellow on opposite side round 

 forehead. Teeth, 23. Ribs, 12. Vertebrae, 66. 



This dolphin is rather smaller than the last (about 

 7 ft. 6 in.), and is confined to the South Atlantic. 



The genus TURSIOPS has the teeth large, 22-26 in 

 number. Vertebral formula: C. 7 ; D. 12, (13); L. 

 16, (i/); Ca. 26 (27) = 6i or 64. Five or six ribs 

 two-headed. Pterygoids in contact. Phalanges: I, i. 



* Nouv. Diet. d'Hist. Nat., ix., 1817, p. 160. 

 t MB, k. Akad. Berlin, 1876, p. 360. 



