4'.>L' Fff . f in India, Ctylon, and Bvrma. 



lo\\ei -than ;tt the prc-cnt day when no glacier in Sikhim i* known to 



de-rclld much bclnW I }.((( tret. 



I Miring the coldest portion of the Glacial epoch, a large jwirt of the 

 higher mountains must have Keen covereil by .-now and iee. and the 

 tropical Oriental fauna which had occupied the range, and which ma\ 

 have retembled that uf the Indian Peninsula more than is the < 

 present, must have lieen driven to the ba-e of the mountain- or exter- 

 minated. Tlu- llolatvtic forms apparently survived in larger numU-is. 

 The Assam Valley and the hill ranges to the southward would afford 

 in damp, sheltered, forest-clad valleys and hill slojH-s a warmer refuge 

 for the Oriental fauna than the open plains of Northern India and the 

 much drier hills of the country south of the Gangetic plain. The 

 Oriental types of the Peninsula generally must have lieeii driven south- 

 wards, and .-'inn- of them, such as /////> and 7V<"/"/">, which must 

 originally have Iteen in touch with their Burmese repi-esentatives, have 

 never returned. It was probable during this cold jieriod that the MB 

 feroiis Nerliudda beds and the deposits in the Karnul caves, were 

 accumulated. The tropical damp-loving l>ravidian fauna, if it in- 

 habited Northern India, must have leen driven out of the country. 

 l"nles> the temperature <f India and Purma generally underwent a 

 considerable diminution, it is not easy to understand how plants and 

 animals of temperate Himalayan types succeeded in reaching the hills 

 of Southern India and Ceylon, as well as those of Burma and tin- 

 Malay Peninsula. 



When the whole country Became warmer again after the cold ei>och 

 had passed away, the Transgangetic fauna appears to ha\e poured into 

 the Himalayas from the eastward. At the present day the compara- 

 tively narrow Brahmaputra plain in Assam is far more extensively fore.-t 

 clad, especiallv to the eastward, than is the much broader Gangetic 

 plain of Northern India, and if. as is. probable, the -anic difference 

 between the two areas existed at the close of the Glacial epoch, it i- 

 to see how much greater the facilities for the migration of a fore-t 

 haunting fauna must have been across the Brahmaputra Valley than 

 over the great plain of the Ganges. This difference alone would give 

 the Transgangetic fauna of Burma an advantage over the Cisganget it- 

 fauna in a race for the vacant Himalayas, even if the latter had not 

 In-en driven farther to the southward than the former, as it probably 

 was during the Glacial epoch. 



The theory, however, is only put forward as a possible explanation 

 t -ome remarkable features in the distribution of Indian vertebrate.-. 

 At the same time it doe- ser\e t<> account for several anomalies of 

 which some solution is neces>ary. If thus accepted, it will add to the 

 evidence, now considerable, in favour of the Glacial epoch having 

 affected the whole world, and not having leeii a partial phenomenon 

 indti'-ed by special conditions, such as local elevation. 



