THE BRITISH MAMMALS : THEIR GENERA AND SPECIES. 39 



The skull is broad and depressed, but the head is globose, the fore- 

 head rising high and rounding over a cushion of fat. There are ten 

 pairs of teeth, which are small and conical, and confined to the front 

 half of the jaws. The dorsal fin is low and triangular, but the 

 flippers are conspicuously long and falcate. In colour theblackfish 

 would be entirely black were it not for a small patch on the breast, 

 from which an irregular narrow stripe generally leads off along the 

 abdomen. There are fifty-eight or fifty-nine vertebras and eleven 

 ribs, of which six are double-headed. ' A noticeable feature of the 

 skull is the great width of the premaxillae beneath which the 

 maxillae are hidden. 



Grampus. Plate xxv. GET ACE A. 



68. griseus, Risso's GRAMPUS. Grey above, with streaks and 



blotches ; muzzle white, flippers grey, tail grey. 



Of this species about a dozen examples are on record, but it is 

 nowhere common. The head is rounded, the dorsal broad and high ; 

 the tail has narrow flukes, and the flippers are long, narrow, and 

 pointed. The beak widens in front of the maxillary notches, and 

 gently tapers to the obtuse extremity. It is just half as long as the 



Risso's GRAMPUS. 

 (Grampus gristus.) 



skull. The upper jaw is the longer, but there are no teeth in it, the 

 only teeth being from three to seven pairs at the outer end of the lower 

 jaw. The grey colour of the upper parts is often faintly streaked 

 with whitish. The length of this dolphin is fifteen feet or less ; it 

 has sixty-eight v.ertebras and twelve ribs, of which half are double- 

 headed. It is not happily named, as almost every dolphin, and 

 especially the Killer, is known to seafaring men as a grampus. 



