Falconer a/id /lis Labours in India 339 



One important conclusion as to the geological date as to the 

 main elevation of the Himmalayahs flows naturally from Dr 

 Falconer's premises. In the Siwalik fauna there were some 

 animals that are common to the later miocenes of Europe. The 

 Hipparion, for example, in miocene times ranged through Russia, 

 Germany, and France, into Spain and Greece, and is found among the 

 Avaifs and strays that compose the red crag of Suffolk. There could 

 therefore in those days have been no geographical barriers to the 

 migration of species, if India be taken as the centre northwards 

 and westwards, if Europe to the south and east. In other words, 

 the chain of mountains passing from the Himmalayahs through 

 Herat and Tehran, and sweeping round the south of the Caspian 

 to join the Caucasus, could not have presented an unbroken 

 barrier to the migration of animals from Europe to India, or vice 

 versa in the miocene epoch. According to Professor Brandt, of 

 St Petersburg, the Steppes of Siberia were inhabited by the 

 mammoth, woolly rhinoceros, and reindeer, while the pleiocene 

 mammalia were living in Europe ; and that as the climate of both 

 Siberia and Euroj^e grew colder, the Siberian fauna gradually 

 advanced to the south and west, until the maximum of cold was 

 reached in the glacial epoch of Europe. But whether this be 

 accepted as true or not, there can be no doubt about the tropical 

 animals of miocene Europe and Southern Russia having been 

 supplanted by those belonging to a type now confined to a 

 temperate or comparatively warm climate ; or that these again 

 were obliged to give way before the invasion of a grew of animals 

 little fitted to endure the severity of an arctic winter. Had there 

 been no geographical barriers, some of these animals, which without 

 exception are confined to the Europeo-Asiatic continent, north of 

 the Himmalayahs, would have found their way to the temperate 

 zone on their southern flanks. There is not even one species that 

 can be considered common to the pleio and pleistocene fauna 

 north of the Himmalayahs and that of the Siwalik hills ; and, there- 

 fore, the presumption amounts almost to a certainty that they were 

 elevated sufficiently high at the close of the miocene epoch, to 

 prevent the invasion of the animals coming from the north; and 

 that they insulated the Indian mammalia as completely as the 

 Straits of Macassar insulate the Australasian fauna. 



Before we pass on to the consideration of Dr Falconer's botanical 

 works, there is a theory which he advances respecting the date of 



