INTRODUCTION". XXU1 



These are practically the same. Each flora consists of members of 

 six ancient, and essentially dominant, Palaeozoic groups, and of 

 three newer, and subsidiary types of a Mesozoic facies. 



Eqotsetales. In the northern type of flora, the Calamites are 

 practically the sole representatives of this group. As already 

 noticed, they make their first appearance during Lower Carboni- 

 ferous times. 



It is interesting to find that in either Lower Carboniferous or 

 Upper Devonian rocks in [New South Wales. Queensland, and 

 Argentina, not only is Arclueocalamites represented, as in Europe, 

 but Calamites has also been recorded from the two former 

 provinces. But in the rocks of Gondwanaland the genus Calamites 

 is unknown. We have in its place two other representatives of 

 the same group, Schizoneura and Phyllotheca, neither of which, 

 however, is so well known, especially as regards its fructification, 

 as the Calamites of the Northern Hemisphere. 



Of the two, Phyllotheca is the more abundant and the more varied 

 genus. It is represented by at least seven species, and has been 

 found in all the four great provinces of Gondwanaland. None of 

 the species, however, are very widely distributed. P. australis, 

 probably the best known, is very similar to the Indian fossil 

 P. indica. P. deliquescens is interesting as occurring not only in 

 Australia, but possibly also in India and Natal, and, with certainty, 

 in Northern Asia. The new species described here as P. Etheridgei, 

 a very beautiful and distinct form, is recorded from Australia, 

 where also the genus as a whole seems to have been much better 

 represented than in any of the three other provinces. Thus, as 

 at present known, Phyllotheca would seem to have been especially 

 characteristic of Australia, where perhaps it may have originated, 

 and subsequently spread rapidly to India and South Africa, and 

 even beyond the boundaries of Gondwanaland. It is found in 

 Asia Minor as early as Upper Carboniferous times, in Russia, 

 Siberia, and the Altai during the Permian period, and in the 

 Triasso - Rhastic epoch it still survived in New South Wales, 

 Tasmania, and possibly in Queensland. It also occurs in the 

 Rhaetic rocks of Tonquin, and in the Lower Jurassic of Europe. 



On the wdiole, "while we may regard Phyllotheca as a successful 

 type of plant life, it was probably also very closely related to 

 Calamites. The fructification of the former is onlv known in detail 



