DOLPHINS 259 



separating it from Delphinus is a negative one the 

 absence of deep lateral palatine grooves." It also 

 comes near. to Tursio ; the main features here which 

 distinguish the two genera are the fewer teeth and 



o o 



more numerous vertebrae. The three orenera are 



O 



quite close together. Some twenty-three species have 

 been assigned to this genus ; but these may be 

 reduced, according to Mr. True, to eio-ht. It is 



o o 



pretty well universally distributed. There seems 

 to be nothino- of interest to record in the habits of 



o 



these dolphins. 



Prodelphinus plagiodon, Cope,* is seven feet in 

 length. Dorsal fin falcate. Colour spotted. Teeth, 

 37. Vertebrae, 69, of which 14 dorsal. 



This dolphin comes from the Atlantic coasts of 

 North America and from the Gulf of Mexico. 



Prodelphinus malayanus, Lesson, f Length about 

 seven feet. Colour uniform ashy. Teeth, 39. 



There is so little either to identify with the genus 

 Prodelphinus^ or to differentiate it as a species (the 

 skull was not described by the original describer of 

 the species but by Schlegel), that it is with great 

 hesitation that it is here included. It is an East 

 Indian species. 



* P. Acad. Nat. Sci. Philadelphia, 1866, p. 296. 

 t Voy. de la Coquille, vol. i., 1826, p. 184. 



