THE ELEPHANT. 269 



food. The neck is slightly indicated; the two nostrils are 

 situated at the upper part of the snout, and the lips are 

 beset with stiff bristles, while tlie mammae are situated 

 between the fore legs. The latter are of moderate length, 

 with five well developed digits, but still fin-like and bent 

 at the elbows. The brain is narrow compared with that of 

 Cetaceans, and the heart is deeply fissured between the 

 ventricles. The manatees of America (Fig. 305) and the 

 dngongof Australia and India (Fig. 306) live in the mouths 

 of large rivers, feeding on sea-weeds and aquatic plants or 

 the grass along the shore. The Floridan manatee {Mana- 

 tus Americanus) grows to a length of from two to nearly 

 three metres (6-14 feet). It ranges from Florida to the 

 Amazons, where it is called Vacca inarina; it ascends that 

 river as far as Pebas, Peru, and is killed and eaten, its 

 flesh resembling beef. Steller's manatee [Rhytina Stelleri) 

 was in the last century found in abundance on the shores 

 of Behring's Island on the coast of Kamtcliatka. Twenty- 

 seven years afterwards (in 1768) it was totally exterminated 

 by the sailors who visited that locality, and only a few im- 

 perfect sl\eletons now exist in the museums of St. Peters- 

 burg and Stockholm. This is the largest Sirenian known: 

 it was over six metres (about twenty feet) in length. It 

 differed remarkably from the other forms in having no 

 teeth, but was provided with a very large, horny, pjilatine 

 plate, and a corresponding one covering the enlarged point 

 of union (symphysis) of the lower jaws. In the Tertiary 

 Period a fossil Sirenian {Halitherium) inhabited the shores 

 of western Europe. 



In the structure of the skull, the nature of their teeth, 

 and their herbivorous habits the Sirenians in a degree con- 

 nect the Cetaceans with the Ungulates. 



Order 7. Prohoscidia. — Only two representatives of this 

 group are now in existence, the Asiatic and African ele- 

 phant, a number of other forms having become extinct. 

 The group is well circumscribed, when we consider the 

 living species, but in the early (Eocene) Tertiary Period 



