steno — sotalia — feresa. 139 



(1) Steno rostratus. (St. r.) 



Delphiiius rostratus, G. Cuvier, Desmarest, and F. Cuvier. 

 Steno frontatus, Gray, Cat. Seals and Whales. 

 Steno rostratus, Gervais, Osteoyr. Cet., 1880. 



Mandible gradually attenuated from behind forwards, 

 not keeled at symphysis. Length of animal about 



9 feet ; length of skeleton about 8 feet ; of skull 

 20 inches. Vertebral formula C^D^gL^^Cdgg = 65. 



1. Mandible, tip broken, length IQh inches. Length of 

 symphysis 5^ inches, one-third length of mandible ; 

 symphysis, transverse diameter ^ inch at free end, at 

 posterior end 1| inch. Posterior end with condyl, 

 coronoid and sharp angle ; height from coronoid to 

 angle 3| inches ; between outer edge of condyls 



7| inches. Teeth moderate, pointed, ^^ .tt;. Mandible 

 « ^ 23 23 



expresses a skull with long, narrow, pointed beak. 



Purchased, Woodcock Collection, 1887. 



XVI. SOTALIA. (So.) 



Sotalia, Gray, Cat. Seals and WJtales, 1860. 



Allied to Steno and Tursiops, in it the pterygoids are 

 separate, the caudal vertebrae are less numerous and 

 the teeth are more numerous (True) ; symphysis of 

 mandible is usually long. Several species have been 

 described. Habitat : some in rivers in China, West 

 Africa, the Amazon, otliers in the South Atlantic, 

 and the coast of Malabar. 



No specimen in Museum. 



XVII. FERESA. (Fe.) 



Feresa, Gray, Suppl. Cat. Seals and Whales, 1871. 

 Ferezia, Flower, Proc. Zool. Soc, 1883 ; Catalogue of Cetacea, 

 1885. 



Defined by Dr Gray as with a flat beak, gradually 

 tapering in front; width at maxillary notch two- 

 thirds of entire length of beak ; lower jaw slender, 

 narrow and thin in front. Teeth not reaching notch, 



10 to 12 in each half of each jaw. Known by only 

 two skulls. South Seas. 



No specimen in Museum. 



