QUADRUPEDS. 209 



the teeth of the porpess are loose in their sockets, while 

 others assert that they are fixed, the former having examin- 

 ed old, the latter young individuals, or even different parts 

 of the same jaw, the middle teeth^ being fixed, the others 

 loose. 



With a dorsal fin. 



121. DELPHINUS. Teeth numerous in both jaws. This 

 is an extensive genus, which CUVIER has proposed to sub- 

 divide into the beaked species (Delphinus), and the short- 

 nosed species (Phocaena), the former represented by the 

 Dolphin, the latter by the Porpess. 



At Plate I. fig. 4. there is a representation of the Por- 

 pess, D. phocana. Fig. 5. represents the teeth, a one in 

 the middle of the lower jaw, and b one in the middle of 

 the upper jaw. Among the British species, some have 

 compressed and obliquely placed teeth, as the phoc<ma>j 

 subulate, as the delphis, conical, as the orca and melas *, 

 and truncated, as the truncatus. It is probable, that 

 the incisors in the upper jaw are limited to two, as in the 

 porpess. 



122. HYPEROODON. Bottle-nose. Two small teeth in 

 front of the lower jaw. H. bidens. See HUNTER, Phil. 

 Trans. 1778, Tab. xixf. 



No dorsal fin. 



123. DELPHINAPTERA. Beluga. D. albicans. This 

 whale is remarkable for the whiteness of its skin, all the 

 others being black on the upper parts. (SCORESBY, Arc. 

 Reg. Tab. xiv. 



* The Delphinus gangeticus of ROXBURGH (Asiatic Researches, vol. vii., 

 and Phil. Trans. 1818), belongs to this group. 



f HUNTER gives the lower jaw in one place, and the upper in another, as 

 the station of the teeth, 



VOL. II. O 



