GENERAL DISTRIBUTION. __________________________________/\__________________________________ / \ NEOTROPICAL| NEARCTIC |PALÆARCTIC | ETHIOPIAN | ORIENTAL | AUSTRALIAN SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS. -----------+-----------+-----------+-----------+-----------+------------ LIVING SPECIES. | | | | | -- -- -- --|-- -- -- --|-- -- -- --|1. 2. 3 -- |-- -- -- --|-- -- -- -- | | | | | EXTINCT SPECIES. | | | | | -- -- -- --|-- -- -- --|1. 2 -- -- |-- -- -- --| 1 -- 3 -- |-- -- -- -- | | | | | The Hippopotamus inhabits all the great rivers of Africa; a distinct species of a smaller size being found on the west coast, and on some of the rivers flowing into Lake Tchad. _Fossil Hippopotami._--Eight extinct species of _Hippopotamus_ are known from Europe and India, the former Post-pliocene or Pliocene, the latter of Upper Miocene age. They ranged as far north as the Thames valley. An extinct genus from the Siwalik Hills, _Merycopotamus_, according to Dr. Falconer connects _Hippopotamus_ with _Anthracotherium_, an extinct form from the Miocene of Europe, allied to the swine. FAMILY 47.--SUIDÆ. (5 Genera, 22 Species.) GENERAL DISTRIBUTION. __________________________________/\__________________________________ / \ NEOTROPICAL| NEARCTIC |PALÆARCTIC | ETHIOPIAN | ORIENTAL | AUSTRALIAN SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS|SUB-REGIONS. -----------+-----------+-----------+-----------+-----------+------------ | | | | | -- 2. 3 -- |-- 2. 3 -- |1. 2. 3. 4 |1. 2. 3. 4 |1. 2. 3. 4 |1. -- -- -- | | | | | The Swine may be divided into three well-marked groups, from peculiarities in their dentition. 1. The Dicotylinæ, or {215}peccaries (1 genus, _Dicotyles_). These offer so many structural differences that they are often classed as a separate family. 2. The true swine (3 genera, _Sus_, _Potamochoerus_, and _Babirusa_); and, 3. The Phacochoerinæ, or wart hogs (1 genus, _Phacochoerus_). These last are also sometimes made into a separate family, but they are hardly so distinct as the Dicotylinæ.