834 REPORT— 1903. 



known as Gangamopteris, and with these grew Schiconeura and Phyllotheca, mem- 

 bers of the Equisetales. In addition to these genera there are others which bear 

 a close resemblance to northern hemisphere types, such as Noeggerathiopsis, a 

 member of the Cordaitales, and several species of Sphenopteris. Similarly, in 

 many parts of India, Glcssopteris has been found in extraordinary abundance in 

 the same company with which it occurs in Australia. In South Africa an 

 identical flora is met with which extends to the Argentine and to other regions of 

 South America. A few members of this southern flora have been recorded from 

 Borneo, and the genus Glosmpteris is said to occur in New Zealand, but the latter 

 statement has been called in question and requires confirmation. It is clear that 

 from South America, through South Africa and India to Australia, there existed 

 a vegetation of uniform character which flourished over a vast southern continent 

 at approximately the same period as that which, in the northern hemisphere and 

 in China, witnessed the growth of the forests whose trees formed the source of our 

 coal-supply. 



Since attention was drawn by Dr. Blanford and other writers to the facts of 

 plant-distribution revealed by a study of the later Palaeozoic floras, it has been 

 generally admitted that during the Permo-Carboniferous era there existed two 

 fairly well-marked botanical provinces. The more familiar and far richer flora 

 occupied a province stretching from the western states of North America across 

 Europe into China and reaching as far as the Zambesi ; the other province was 

 occupied by a less varied assemblage of plants, characterised by the abundance of 

 Glossopteris, Gangamopteris, Neuvopteridimn, Noeggerathiopsis, Schizoneiira, and 

 other genera, stretching from South America through India to Australia. 



Two questions at once suggest themselves : firstly, were these two botanical 

 provinces defined by well-marked boundaries, or did they dovetail into one another 

 at certain points ? Secondly, is there any probable explanation of this difl'erence 

 between northern and southern floras, a feature not shown either by the preceding 

 Devonian and Lower Carboniferous or by the succeeding Lower Mesozoic floras ? 



In Brazil, Professor Zeiller has recorded the occurrence of a flora including 

 Lepidophloios, a well-known European member of the Lycopods, associated with 

 such characteristic southern types as Gangamopteris and Noeggerathiopsis. 

 Similarly from the Transvaal a European species of Sigillaria, with a Lepidoden- 

 droid plant, and another northern genus, PsygmojjJiyllum, have been found in beds 

 containing Glossopteris, Gangamo^jteris, Noeggerathiojjsis, Neuroptteridium, and other 

 members of the so-called Glossopteris flora. In India, the Glossopteris flora 

 exhibits an entire absence of Lepidodendron, Calamites, Sigillaria, and other com- 

 mon northern genera, while Sjjfieiiop/iglhan is represented by a single species. 

 The Australian Permo-Carboniferous flora is also characterised by the absence of 

 the great majority of the northern types. Until a few years ago the genus 

 Glossopteris had not been discovered in Europe, but in 1897 Professor Amalitzky 

 recorded the occurrence of this genus in association with Gangamopteris in 

 Permian strata in Northern Russia. 



We see, then, that in Brazil and South Africa the Glossopteris flora and the 

 northern flora overlapped, but the former was the dominant partner. On the 

 other hand, in rocks belonging to a somewhat higher horizon in Russia, we meet 

 with a northern extension of the Glossopteris flora. The accompanying map (p. 835) 

 serves better than a detailed description to illustrate the geographical distribution 

 of these two types of vegetation in the Permo-Carboniferous era. 



There is little doubt that the diflerences between the flora of the southern 

 continent, that existed towards the close of the Carboniferous and during the 

 succeeding Permian period, and that which flourished farther north have in some 

 respects been exaggerated ; geographical separation has played too conspicuous a 

 part in influencing botanical nomenclature. Granting the existence of identical 

 genera or representative types, there remains a striking difference between the two 

 provinces into which the Permo-Carboniferous vegetation was divided. As regards 

 an explanation of this fact, we can only hazard a guess ; as Dr. Blanford and 

 others have pointed out, there is a probable solution to hand. Briefly stated, the 

 Upper Palpeozoic plant-bearing strata of India, South America, Australia, and 



