Xl INTRODUCTION. 



important discovery was the first direct evidence to be gained 

 from India bearing on the age of the Glossopteris flora. In the 

 previous year, Griesbach ' had shown that Vertebraria occurs in 

 beds which overlie similar glacial deposits in Afghanistan. 



Still more recently, the existence of a well - marked Glacial 

 period at the beginning of Periuo-Carboniferous times has received 

 yet wider confirmation. The Dwyka conglomerate of South Africa 

 is of glacial origin, and occupies a similar position with regard to 

 the Glossopteris - bearing beds of that province as in India and 

 Australia. Further, in 1888, Derby 2 showed that glacial deposits 

 belonging to the same period are also developed in Brazil. 



Within the last two years, Noetling 3 has found Gangamopteris in 

 the Salt Range of Kashmir in beds below those containing Permian 

 invertebrata. 



Amalitzky 4 has also discovered the Glossopteris flora in Russia 

 on a horizon intermediate between a plant-bearing series of Lower 

 Permian age and deposits containing Upper Zechstein mollusca. 



Further, there is the botanical evidence of the Glossopteris flora 

 itself. The representatives of two groups associated with that 

 flora, the Lycopods and the Sphenophyllales, are generically, and 

 sometimes even specifically, identical with those of the northern 

 type of vegetation. Among the earlier types of a Mesozoic facies, 

 such as Tceniopteris, Voltzia, and Rkipidopxis, which begin to come 

 in during Permo-Carboniferous times in both the northern and 

 southern floras, there is also generic identity. Also the essentially 

 Palaeozoic types, which at this period were dominant elements in 

 the flora, all belong, so far as their botanical affinities are known, 

 to the same great classes of plants as the members of the flora of 

 the Northern Hemisphere. 



At the close of Permo-Carboniferous times, a change took place 

 in the flora of Gondwanaland. It is of great interest to find that 

 we have an almost continuous succession of plant-bearing sediments 

 in more than one province of this continental region, in part of 

 Palaeozoic, and in part of Mesozoic age. This is the case in India 



1 Griesbach (85), p. 62. 



2 See W. T. Blanford (95), (96). 



3 Noetling (03) ; Seward & Woodward (05). 

 1 Amalitzky (97), (01). 



