106 CETACEA. 



SECTION OF GENERA. 



a. Head shortly beaked. Nose of skull moderate. Triangle 



on hinder part of beak elongate, produced before the teeth- 

 line. Palate flat. Teeth |-g. 



t Beak scarcely produced. Nose of skull rather depressed, 

 scarcely longer than the brain-cavity. Teeth |f-f. 

 Species No. 1-3. 



ft Beak short. Nose of skull thick, conical, convex above, 

 half as long as the head. 



* Beak of skull rather thick, and rather swollen on the sides. 



No. 4-7- 



** Beak of skull rather thick, conical, evenly tapering. No. 89 . 

 *** Beak of skull slender, subcylindrioal. No. 10-11. 



b. Head longly beaked. Nose of skull slender, light, rather 



depressed, especially in front, much longer than the head. 

 Teeth Jg-f g. 



* Skull flattened behind. Triangle to the teeth-line. Palate 



flat, not grooved on the side. No. 12-15. 



** Skull roundish. Triangle just to the teeth-line. Palate 

 ivith a deep groove on each side and a high central ridge 

 behind. 



t Beak moderate, 1| the length of the brain-cavity. Teeth |4 

 or !. No. 16-20. 



ft Beak of skull twice as long as the brain-cavity . Teeth ff-f g. 

 No. 21. 



: * Skull round. Triangle not reaching to the teeth-line. 

 Palate convex, with a very concave line on the hinder part 

 of each side. Beak twice as long as the head. Teeth f. 

 No. 22. 



a. Head shortly beaked. Nose of skull moderate. Triangle 

 on hinder part of beak elongate, produced before the teeth- 

 line. Palate flat. Teeth H-J. 



t Beak scarcely produced. Nose of skull rather depressed, 

 scarcely longer than the brain-cavity. Teeth f f-f . Ce- 

 phalorhynchus. 



Cephalorhynchus, F. Cuvier, Cetac. 

 Grampus, pars, Gray, Spic. Zool. 2, 1828. 



