INTRODUCTION. 



the Rhoetic of Tonquin. In the floras of both the northern and 

 southern Permo-Carboniferous continents, a few Cycads are found, 

 which represent the gradual incomings of a great group, essentially 

 of Mesozoic affinities, but in the latter flora the Cycadophyta are, 

 if anything, less abundant than in the former. There is no good 

 evidence to show that the leaves named Pterophyttum hurdwanense 

 and Glossozamites Stoliczlcanus by Feistmantel, and Sphenozamites 

 multinervis by Kurtz, are really referable to the Cycadophyta. 

 The former is possibly a Teeniopteris, while the two latter are 

 almost certainly leaves allied to NoeggeratMopsis Hislopi. 



Ginkgoales (?). The genera somewhat doubtfully assigned to 

 the Ginkgoales are rather more numerous than the Cycadophyta. 

 Four species occur, belonging to three genera, of which two 

 are only known so far from the Palaeozoic rocks. One species, 

 Rhipidopsis ginhgoides, is identical with a plant from the Permian 

 of Russia, while another, Psygmophyttum Kidstoni, may be closely 

 compared with members of the genus from the Carboniferous 

 and Permian of Europe. In this group, again, we have another 

 instance of the gradual incoming of a type of plant which reached 

 its maximum during the Mesozoic period, though such members 

 as are associated with the Glossopteris flora would appear to be 

 early types hardly extending beyond the Palaeozoic rocks. 



Conifeuales. The Coniferae on the whole are few in number ; 

 the most interesting genus being Voltzia, which appears first in 

 the Carboniferous of Europe, and is especially abundant in the 

 Triusso-Rhaetic rocks of the Northern Hemisphere. Of the other 

 five genera recorded, three are doubtful attributions, and may be 

 neglected here. Araucarites, so far only recorded from the Mesozoic 

 rocks, has been found in India, but the exact horizon of the beds 

 in which it occurs is uncertain. There remains Cyelopitys, only 

 known elsewhere from the Permian of Europe. Although in Voltzia 

 we have a type associated with the Glossopteris flora, which would 

 appear to be chiefly of a Mesozoic facies, we notice that the 

 Couiferse, as a whole, are even less abundant than in the Northern 

 flora, and that several of the representatives present are among the 

 earliest to appear in the Northern Hemisphere. 



Nearly all the fossil plants of the Glossopteris flora occur as 

 casts ur impressions, in which the anatomical structure is not 



