576 DELPHINID.E. 



Genus ORCA, Wagler (1830). 



Size very large. No beak ; head conical and depressed. Dorsal 

 fin erect, very high, especially in the male. Pectoral fins large, 

 broadly ovate.- 



Teeth few, 10 to 13 on each side above and below, very large, 

 often an inch or more in diameter, oval in section, the longer 

 diameter across the jaw. Kostrum broad. Pterygoids separate. 

 Vertebrae: C. 7, D. 11-32, L. 9-10,0. 24=51 or 52. 



The animals of this genus are highly predatory, living on seals, 

 whales, and other cetaceans, besides fish. They associate in small 

 herds, and are said to attack and kill even the largest whales. 

 Many species have been described, but it is quite uncertain how far 

 they can be distinguished. 



382. Orca, sp. (0. gladiator ? The Grampus or Killer}. 



? Delphinus orca, L. Syst. Nat. i, p. 108 (1766). 



? Delphinus gladiator, Bonnaterre, Get. p. 22 (1789). 



? Orca gladiator, Gray, Zool. Ereb. Sf Terror, p. 33 ; Flower, P. Z. S. 



1883, p. -5075 True, Delphinidce, p. 187, pl.~xlv, figs. 1, 2. 

 Cetacean, Hotdsworth, P. Z. S. 1872, p. 



p. 583 (figs. p. 584). 



A cetacean was seen by Mr. E. W. H. IToldsworth in April 

 1868 off the west coast of Ceylon, and briefly described by him, 

 the description being illustrated by sketches. The animal appeared 

 to be about 25 feet long, and was furnished with a remarkable 

 straight, erect, narrow dorsal fin about 5 feet high. As figured 

 the fin appears scarcely a foot broad, with the anterior and posterior 

 margins nearly parallel. 



Fig. 188. Grampus or Killer, Orca gladiator. (Flower, art. " Mammalia,' 

 ' Encyclopaedia Britannica.') 



The only cetacean with a fin of this kind is Orca, but generally 

 the dorsal fin, though very high, especially in the male, is re- 

 presented as triangular. There is a skull of 0. gladiator from the 

 Seychelle Islands in the British Museum, so this species is an 

 inhabitant of the Indian Ocean. 0. gladiator grows to about 20 

 feet in length, the teeth are 10-13 in number on each side above 

 and below, and the coloration is peculiar the upper parts generally, 

 with the fins, black ; the lower to the vent white, but the white 



