90 THE NEW SPECIES OF PTEROPHYLLUM. 



The order Cycadese is one that in our time is dispersed in little 

 groups over large areas. Species are met with in the southern 

 part of the United States, in tropical America, in Australia, 

 in the south of Japan, in southern and subtropical Africa, and 

 in the archipelagoes and coasts of the Indian Ocean. Australia 

 has three living genera — Cycas, with pinnate leaves, the pinnae 

 with the midrib prominent beneath ; Macrozamia with pinnate 

 leaves devoid of midrib ; and Bowenia with bipinnate leaves. In 

 the Flora Australiensis these genera are credited with seven 

 species in all ; in Baron F. von Mueller's Census for 1889 the 

 number is fourteen, thirteen of which are peculiar to Australia ; 

 the genus Cycas has a wide range from Madagascar on the 

 west to Japan on the north-east. 



The fossil remains of Cycadete seem to have attained their 

 greatest development in the Mesozoic formations, especially in 

 the series of beds of the Jurassic system ; and at that period 

 they were generally distributed over the northern hemisphere. 

 Few Palaeozoic forms are known ; and these few are chiefly 

 remains of stems from the Permian formations and the coal- 

 measures ; but among these are some undoubted Cycadaceous 

 leaves, which have been mainly referred to the genus Pterophyl- 

 lum. Very little can be said of the position occupied by Cycads 

 in the Tertiary flora, as this flora has only been deeply studied 

 in Europe, and to a less extent in the Arctic zone — regions where 

 these plants no longer live. In Europe they existed during the 

 Tertiary period, but in much diminished numbers, and they were 

 confined to a small number of genera. 



In Dr. Feistmantel's work on the Geological and Palfeonto- 

 logical relations of ihe coal and plant-bearing beds of Palseozoie 

 and Mesozoic Age in Eastern Australia and Tasmania, he figures 

 and describes eight species of fossil Cycads, ranged under four 

 genera. In the Geology and Palaeontology of Queensland and 

 New Guinea, Mr. R. Etheridge describes ten species of fossil 

 Cycads divided between four genera, including two species of 

 Pterophyllum. 



When lately examining, by the kind permission of Mr. R. 

 L. Jack, a number of fossils obtained from a railway cutting at 

 Yeronga, I found, among other plants, the remains of two 

 species of Pterophyllum, which have not yet been described. 



