3. DELPHINUS. 67 



4. Steno P rostratus, &/•«//, C«rf. S. Sf W. p. 238. 



Dauphin de Breda, Owner, Oss. Fuss. vol. v. p. 400. 



Inhab. North Sea. 



2. SOTALIA. 



Sotalia, Gray, I. c. pp. 393, 401 ; Synops. Whales Sf Dolph. p. 6. 



Dorsal fin distinct. Beak depressed, rather longer than the brain- 

 cavity. Teeth slender, conical. Palate flat behind. Pectoral fin 

 ovate, obliquely truncated at the end ; hand shorter than the arm- 

 bones. Carpal bones small. Scapula broad. Acromion broad. 



Vertebra 55 :— C. 7. D. 12. L. 14. C. 22. 



Scarcely distinct from Steno. 



1. Sotalia guianensis. 



Sotalia guianensis, Gray, I. c. p. 401 ; Synops. Whales Sf Dolph. p. 0. 

 Tursio guianensis, Gray, 1. c. p. 257. 



Delphinus guianensis, Van Beneden, Mem. Acad. JBrttx. p. 27, t. 2 

 (skeleton), torn. xvi. tab. 2. figs. 1 and 2. 



Inhab. British Guiana. 



Teeth 28 or 29. Pectoral fin very broad : fingers five ; the index 

 the longest, the thumb and little finger the least developed. The 

 caudal vertebrae very strong. The first two of the cervical vertebrae 

 united, the five others separate. Sternum in three pieces. 



Tribe II. DELPHININA. 



Delphinina, Gray, Synops. Whales Sf Dolph. p. 5. 

 Head beaked. Teeth conical. Beak of the skull elongate, longer 

 than the brain-cavity, depressed, broad, shelving on the sides. Nasal 

 triangle short. Symphysis of the lower jaw very short, sloping. 

 Dorsal fin subcentral, rarely wanting. 



a. Beak elongate. Palate with a deep groove on each side behind. 



3. DELPHINUS. 



Delphinus, Gray, I. c. pp. 230, 239, 393 ; Synops. Whales $ Dolph. 

 p. 5. 



Beak elongate. Dorsal fin distinct. Teeth small, slender, five or 

 six in an inch. Fingers elongate, unequal ; the second much the 

 longest, 8- or 9-jointed ; third elongate, about three-fourths the 

 length ; the rest short. 



Foetus and tongue figured, t. 2G. f. 2 of Synops. Whales and 

 Dolph. 



f2 



