I424 CLASS MAMMALIA. 



genus has been obtained from the Miocene of Malta, while other 

 forms occur in the Pliocene of the Crimea and elsewhere. Remains 

 from the Miocene of Virginia have been described under the name 

 of Phoca Wymani, and others from the Pliocene of South Carolina 

 have likewise been referred to the same genus. 



Family Trichechid^e. — The Walruses, which are in some re- 

 spects intermediate between the other two families, are readily dis- 

 tinguished by their enormous upper canines. The existing Arctic 

 Tricheckus rosmarus occurs fossil in the Norfolk Forest-bed, and an 

 allied species, T. Huxleyi, in the Red Crag ; while the names Alach- 

 therium and Trichechodon have been applied to closely allied, if not 

 generically identical, forms from the Belgian Crag. 



Family Otariid^e. — This family, in which the number of the 



incisors is invariably -, is almost unknown in a fossil state, 



2 



although some writers have considered that certain genera here 

 included in the Phocldce should be referred to it. Remains 

 of existing species of the type genus Otaria have, however, been 

 obtained from Prehistoric or Pleistocene beds in New Zealand, and 

 also from the Pleistocene of South America. 



Suborder 2. Carnivora Vera. — In the typical Carnivora the 

 brain is relatively large, and the hemispheres are elongated, and 

 always marked by three or four folds. The fore limbs never have 

 the first digit, or the hind limbs the first and the fifth digits longer 

 than all the rest. There is always a more or less distinctly defined 

 carnassial tooth in each jaw ; the teeth in front of such carnassial 

 being always more or less compressed and pointed, while those 

 behind the same are broad and tuberculated. And it appears from 

 the dentition of the suborder Creodonta that these tuberculated 

 posterior teeth are the most specialised. The upper carnassial 

 (^ 4 , fig. 1302), as being the hindmost of those teeth which have 

 milk predecessors, is reckoned as the last premolar ; and it usually 

 consists of an outer compressed blade, generally furnished with two 

 (fig. 1302), but occasionally (fig. 1325) with three cusps or lobes, 

 and of an inner tubercle (fig. 1325). This tubercle is generally 

 placed near the anterior extremity of the crown, and is of medium 

 size; but in some instances, as in Machcerodus (fig. 1334), it may 

 be almost absent, while in others, as in the Otters (fig. 1303), it 

 attains a great development. The lower carnassial (m 1 in the man- 

 dible of fig. 1302), as the most anterior of the teeth without milk 

 predecessors, is reckoned as the first of the true molar series. 

 Typically, the crown of this tooth (fig. 1302) consists of an an- 

 terior blade, composed of two compressed cusps or lobes, and an 

 inner cusp (fig. 1318), and of a hind talon. In the Wolf (fig. 1302) 

 all these elements are well developed ; but sometimes, as in Fells 



