722 MAMMALIA [CH. 



Family 1. Otariidae. 



Pinnipedia still retaining a trace of the external ear, 

 and capable of turning the hind-limbs forward so as to 

 walk on land. 



Ex. Otaria. 



Family 2. Trichechidae. 



Pinnipedia devoid of external ear, but capable of walking 

 on land : the upper canines form long tusks. 

 Ex. Trichechus. 



Family 3. Phocidae. 



Pinnipedia devoid of external ear, and incapable of 

 turning the feet forward, so that when on land they can 

 (%ly wriggle along with the help of their anterior limbs: 

 the canines not specially enlarged. 



Ex. Phoca. 



Order V. Cetacea. 



Large aquatic Eutheria which have lost the hind-limbs and 

 have developed horizontal flukes on the tail. The fore-limb is 

 a paddle : the cranium is globular and the teats are posterior. 



Sub-order 1. Mystacoceti. 



Cetacea devoid of teeth in the adult and with plates of 

 whalebone in the mouth. 



Ex. Balaena, Balaenoptera. 



Sub-order 2. Odontoeeti. 



Cetacea with teeth at any rate on the lower jaw and no 

 whalebone. 



Ex. Physeter, Globicephalus, Delphinapterus, Phocaena. 



Order VI. Ungulata. 



Eutheria with limbs adapted entirely for progression, the 

 terminal phalanx of each functional digit is enclosed in a short 

 blunt nail. 



Sub-order 1. Sub-ungulata. 



Ungulata with short subequal toes, and with the bones of 

 the carpus and tarsus arranged in parallel longitudinal series. 

 Family 1. Hyracidae. 



Small Sub-ungulata with a very short snout : a pair of 

 chisel-like incisors in each jaw. 

 Ex. Hyrax (Procavia). 



