ELEPHANTS. 365 



the continent. The remains of the existing species of porcupine 

 and beaver (cave of Gailenreuth) are found in the Quaternary 

 deposits. 



The rodent fauna of the American (western) Tertiaries is very 

 closely related to the European, a large number of identical, or 

 analogous, genera being represented. This is especially the case 

 with the forms belonging to the Miocene period, where, in addi- 

 tion to a considerable number of extinct types, we find such forms as 

 Steneofiber, true beavers (Castor — several species), squirrels (Sci- 

 urus), vesper-mice (Hesperomys), and not impossibly also the true 

 porcupine (Hystrix). Eumys does not appear to differ essentially 

 from Cricetodon, while Ischyromys represents Sciuromys. A dis- 

 tinctive feature separating the American from the European fauna 

 is the introduction of the hares, which are not only represented by 

 forms now no longer living (Palajolagus), but also by the modern 

 genus Lepus. In the Pliocene fauna there is a still further approxi- 

 mation to the fauna of the present day in the appearance of an 

 additional number of recent genera — Erethizon (Canada porcupine), 

 Geomys (gopher). The last genus is also found in the Quaternary 

 deposits, as also other members of the same family (Saccomys), and 

 the vole, musk-rat, wood-chuck, ground-squirrel, wood-hare (Lepus 

 sylvaticus), beaver, and a form of capybara (Hydrochaerus .^sopi). 

 Castoroides Ohioensis, the largest of all known rodents, recent 

 or fossil, appears to have been of the dimensions of the black 

 bear. 



Froboscidea (Elephants). — At the present day there are but 

 two living species of this order known — the one being the Asiatic 

 elephant, Elephas Indicus, which inhabits the forest lands of In- 

 dia and Southeast Asia generally, with the islands of Ceylon, Suma- 

 tra, and (?) Borneo, and the other the African elephant, E. (Loxodon) 

 Africanus, a native of the greater part of the continent of Africa 

 south of the Sahara. The insular Asiatic form is by some authors 

 considered to represent a distinct species, to which the name E. 

 Sumatranus has been applied. Although now restricted in a gen- 

 eral way to the warmer parts of the earth's surface, there can be 

 no doubt that the range of the species was very much greater at an 

 earlier period of the earth's history than it is at present, seeing 

 how very broad was the distribution of the genus. The remains 

 of elephants undistinguishable from the African form have been 



