HIPPOPOTAMI. 453 



the following year, where, as already mentioned, it lived till 1878. This was a 

 male, and although a consort was obtained for it in 1853, no young were produced 

 till 1871. The calf born in that year did not, however, long survive, and the same 

 untimely fate also befell a second calf produced in the spring of the following year. 

 A third calf was born in the autumn of 1872, and is still living (1894). 



Pigmy The Liberian or pigmy hippopotamus (H. liberiensis) from 



Hippopotamus. Western Africa is a much smaller animal, not exceeding a pig in 

 dimensions, and weighing only about 400 Ibs. This species differs structurally from 

 the common one in having only a single pair of incisor teeth in the lower jaw, 

 although a small representative of the second pair may sometimes occur on one 

 side. The colour of the back is slaty black, while that of the under-parts is dirty 

 greyish white, and the sides greenish slaty grey. The height at the shoulder is 

 about 2 feet 6 inches, and the total length 6 feet, of which 7 inches are occupied 

 by the tail. 



This diminutive species appears to be confined to Upper Guinea, 



and according to Herr Btittikofer is found only in swamps and damp 



forests, and not in rivers. Its habits are said, indeed, to be more like those of wild 



swine than those of its gigantic cousin, and, instead of traversing well-beaten paths, 



it wanders great distances in the woods. The author quoted is uncertain whether 



the Liberian hippopotamus is nocturnal or diurnal in its habits, although he is 



inclined to believe that it is the latter. It is, however, certain that it lives either 



solitary or in pairs, and that it never associates in troops like the larger species. 



Extinct Among extinct species of the genus, the Maltese hippopotamus 



Hippopotami. ([ minutus), of which the remains are found in such enormous 

 quantities in the caverns of Malta and Sicily, appears to have been no larger than 

 the Liberian species, though it resembled the ordinary living African one in the 

 number of its lower incisor teeth. Intermediate in size between the Maltese and 

 the common hippopotamus was Pentland's hippopotamus (H. pentlandi), found in 

 the same deposits as the former. The vast quantities in which the remains of these 

 two extinct species are found in the Sicilian caves presents a puzzle, since hippo- 

 potami are not the sort of animals which one would expect to frequent such 

 habitations. Some years ago many shiploads of teeth and bones of these species 

 were imported into England from Palermo for the manufacture of charcoal. 



Although hippopotami are now quite unknown in India, during the Pleistocene 

 and Pliocene epochs they were abundant in that country. In the Pleistocene of the 

 Narbada Valley in Central India remains of two species of the genus are met with ; 

 one of these (H. palceindiciis) being characterised by the presence on each side of 

 the lower jaw of a small incisor tooth between the two larger ones, corresponding 

 to those of the common African hippopotamus; while in the second Narbada 

 species (H. namadicus) both upper and lower jaws were provided with three 

 nearly equal-sized pairs of incisor teeth. The same condition also obtains in the 

 Siwalik hippopotamus (H. sivalensis) from the Pliocene rocks at the foot of the 

 Himalaya, and likewise in the Pliocene Burmese hippopotamus (H. iravadicus) and 

 the Algerian hippopotamus (H. bonariensis), which was likewise of Pliocene age. 

 An extinct hippopotamus (H. lemerlei) has also been discovered in the superficial 

 deposits of Madagascar. 



