NATURAL HISTORY OF SOUTH AFRICA 



Sub-order: ODONTOCETI 



Family : Physeterid^ 



{Sperm Whales) 



Whales with permanent teeth in the lower jaw. No baleen or 

 whalebone. No functional teeth in upper jaw. The nostrils 

 unite before they reach the surface. Large cavity in the top of 

 the skull. Sternal ribs not ossified. Females smaller than the 

 males. 



South African species 



I. Physeter macrocephalus, Linn, The Sperm Whale or Cachalot. 



Syst. Nat., 12th ed., p. 107 (1766). 

 I. Kogia brevicepSy Gray. The Small Sperm Whale. Zool. 



Ereb. and Terror, p. 22 (1846); Flowers: List of Cetacea, 



B.M., p. 9 (1885). 



Family : Ziphiid^ 

 (Bottle-nosed and Beaked Whales) 



Functional dentition reduced to one or two pairs of large teeth 

 in lower jaw. These are larger in males than in females. 



Skull prolonged into a beak of strong ivory-like bone. First 

 two cervical vertebrae fused. Flippers placed higher up than in 

 Sperm Whales. 



I. Tiiphius cavirostris, Cuv. Cuvier's Whale. Ossemens foss, 

 2nd ed., v. p. 352 (1823) ; Flower, Trans. Zool. Soc, viii. 

 p. 207 (1872). 



1. Mesoplodon layardi, Gray. Layard's Beaked Whale. Trans. 



Zool. Soc, viii. p. 211 (1872). 



2. Mesoplodon densirostris. Flower. Blainville's Beaked Whale. 



Trans. Zool. Soc, x. p. 416 (1878). 



3. Mesoplodon bidens, Sow. Sowerby's Beaked Whale. 



Family : Delphinid^ 

 (Killers, Porpoises and Dolphins) 



Numerous teeth in upper and lower jaws. The two branches 

 of the lower jaw are very much less than half the whole length 

 of the jaw itself. Ribs four to five with double heads. Skull 

 without crests. Sternal ribs ossified firmly. 



266 



