XV111 INTRODUCTION. 



great Southern Pernio - Carboniferous continent lias been dis- 

 tinguished by Suess ] as Gondwanaland, a term derived from 

 tbe great series of fresh-water sediments in India, to which 

 Medlicott gave the name, Gondwana system. Only the lower 

 part, however, of the Gondwana rocks of India belong to the 

 period under discussion. 



It is with the fossil plants of Gondwanaland that we are here 

 concerned. This flora is especially characterised by the frequent 

 occurrence of Glossopteris, a fern-like plant not only of wide 

 distribution but often found in such extreme abundance that 

 some of the rocks of Gondwanaland appear to be largely composed 

 of impressions of its fronds. Thus the southern type of Permo- 

 Carboniferous flora has come to be known as the Glossopteris 

 flora, a name first used by Neumayr ~ to distinguish it from the 

 dissimilar, but more or less contemporaneous flora of the Northern 

 Hemisphere. The Glossopteris flora is found typically developed 

 in four great provinces of Gondwanaland, viz., India, Australia 

 with Tasmania, Southern Africa, and South America. The 

 accompanying map shows roughly the relative distribution of 

 the Northern and Southern Permo-Carboniferous floras. At the 

 close of the Permo-Carboniferous period, some members of the 

 flora had become extinct, while others still survived and con- 

 tributed to the vegetation of Triasso-Rhaetic times, though in 

 a subordinate degree ; the survivors being no longer dominant 

 elements in the vegetation of the early Mesozoic rocks. 



In discussing this flora three main points have to be considered : 

 (1) its botanical affinities, (2) its distribution in space, (3) the 

 evidence as to its age and distribution in time. We may commence 

 with a brief account of the botanical affinities of the Glossopteris 

 flora. At the same time it must be borne in mind that our 

 knowledge at present on this point is still very imperfect, and 

 consequently some of the conclusions arrived at must be regarded 

 as of a provisional nature. 



1 Suess [85), vol. i. p. 76S. 



2 Neumayr (87), p. 191. 



