The bones of the skull are elevated to form a high crest above and behind the nares. The rostrum is very massive and wide, but gradually tapers to the apex, and is concave. Lower jaw very long and narrow. Atlas free, but all the other cervical vertebræ united into a solid mass. Vertebral formula: cervicals 7, dorsals 11, lumbars 8, caudals 24. Total, 50. Habitat: cosmopolitan, in warm currents.
KILLER WHALE, ORCA, GRAMPUS, THRESHER
Orca orca (Linn.)
Form robust. Head pointed. Heavy pointed conical teeth in both jaws. An extremely high dorsal fin. The color is black, with an elliptical white spot on each side of head. The throat and breast are white and there is a trident-shaped area of white on the belly and flanks. A white or grayish patch is usually present just behind the dorsal fin. The flukes above are black, and below white except for a black band on the posterior margins and tips. Greatest length, 30 feet.
Rostrum about equal in length to the cranial part of the skull, broad and flattened above, rounded in front. Teeth usually twelve in each jaw. Vertebral formula: cervicals 7, dorsals 11–12, lumbars 10, caudals 53. Total, 51–52. Habitat: cosmopolitan.
WHITE WHALE, BELUGA, MARSOUIN BLANC
Delphinapterus leucas (Pallas)
Form robust. Head very small and marked off from body by an ill-defined neck. No dorsal fin. Pectoral fins very broad and upturned. The color is pure white in the adult, except for a very narrow band of brownish on the edges of the flukes and flippers. The young are entirely brownish.
Skull rather narrow and elongated. Eight to ten teeth in both jaws—cervical vertebræ all free. Vertebral formula: cervicals 7, dorsals 11, lumbars 9, caudals 23. Total, 50. Habitat: North Atlantic and North Pacific.
BLACKFISH, PILOT WHALE, CA’ING OR GRINDHVAL
Globicephalus melas (Traill)
Form robust. Head large and very round. Dorsal fin thick and triangular. Pectoral fins very long and narrow.
The color is black throughout, except for a narrow fountain-shaped area of white on the throat, breast and belly. Greatest length, 30 feet.