354 AUSTRALIAN, SOUTH AFRICAN, AND INDIAN COAL-MEASURES, 



greater and more extensive emergence of these regions than had 

 occurred in the previous coal-forming periods. Yet the two 

 things are at least not inconsistent, and the hypothesis will help 

 to account for many otherwise inexplicable or difficult points. 



Supposing then, since the supposition is allowable as such, that 

 during this Newcastle period the western and eastern groups of 

 islands (Australia and New Zealand) were both at the same time 

 united (by emergence) with the Antarctic lands, and supposing 

 also that the southern extremity of the African continent was in 

 like manner, and at the same time, prolonged to meet a northern 

 extension of the same, we should once again have two Oceanic 

 resions, the sea between Australia and New Zealand on the one 

 side, and the sea between Australia and Africa on the other, 

 practically closed against all cold currents and continually warmed 

 in their higher latitudes by the equatorial currents generated 

 within the tropics. Such conditions would induce for certain the 

 general dispersion along the maritime districts of those elements 

 of the Australian flora and fauna which had been severally 

 developed by one cause or another in such a way as to qualify 

 them for a general occupation of the new territories ofiered by 

 emergence and for a contest on advantageous terms with the 

 other competitors. 



Thus the Glossojyte^^is flora spread into the Antarctic lands, 

 among them east and west to New Zealand and South Africa, and 

 perhaps also northwards from Australia across the equator 

 towards India, then an insular tract in processs of emergence, 

 occupied in all probability by a low and feeble flora, and open as 

 India has ever been to the first invader. 



It is unnecessary to enter into further detail. The hypothesis 

 is sufiiciently stated, but remains as it began, a hypothesis, in- 

 volving the assumption that the evidence of the existence of 

 Glossopteris, &c., in South Africa and New Zealand does not 

 indicate synchronism with the Glossojyteris series of New South 

 Wales. 



The next period in the New South Wales series (the blank in 

 the record, which succeeds to the Newcastle Coal Measures) 

 is again one of extreme change in the flora and on land. 



