IV. 

 CYCADEAE, MEDULLOSEAE. 



THE remains of Cycadeae attain their greatest development in the 

 Mesozoic formations, especially in the series of beds of the Jurassic system ; 

 there can be no doubt that they were generally distributed during that 

 period of time over the northern hemisphere. Comparatively few Palaeo- 

 zoic forms are known, and most of these are remains of stems from the 

 Permian formation and from the Coal-measures. Undoubted leaves of 

 Cycadeae have been found but very rarely in both these systems, and have 

 been described and figured in Saporta and Marion 1 (Pterophyllum Grand' 

 Euryanum, Sap. et Mar., and Sphenozamites Rochei, Ren. 2 ) from the Coal- 

 measures of St. Etienne and Autun, in Geinitz 3 (Pterophyllum Cottaeanum, 

 Gein.) from the Rothliegende of Zwickau, and in Sandberger 4 (Pterophyl- 

 lum blechnoides, Sandb.) from the Upper Coal-measures of Oppenau in 

 Baden. A leaf also which is said to come from the Coal-measures of 

 Eastern Russia is figured in Eichwald 5 and named Pterophyllum inflexum, 

 Eichw., and Renault and Zeiller 6 mention a Zamites carbonarius from the 

 coal of Commentry. Several others described by Goppert 7 are not above 

 suspicion. 



The Cycadeae are still tolerably numerous in the lower Chalk, but 

 after the Cenomanian beds the group diminishes greatly in importance. 

 It must not however be forgotten that the Tertiary flora is really known 

 to any great extent only in Europe and perhaps in the Arctic Zone, 

 regions in which Cycads no longer live, and from which they may have 

 gradually disappeared during the period of the Chalk. That they 

 were still to be found in the South of Europe in Tertiary times, though 

 few in number, is shown by some single specimens from the Lower 

 Miocene ; we have, for example, Zamites epibius, Sap. 8 , from Bonnieux 

 in the Department of Vaucluse and Encephalartos Gorceixianus, Sap. 9 , 

 from Kumi in Euboea, both represented by leaves which certainly have the 



1 Saporta et Marion (2), p. 109. 2 There is a mistake in the explanation of the woodcuts in 



the work, that which is said of B referring really to A, and vice versa. s Geinitz (1) and (4). 



* Sandberger (1). 5 Eichwald (1), vol. i, t. 15. e Zeiller (11). 7 Goppert (7). 



* de Saporta (2), p. 116. 9 de Saporta (2), p. 116, an (10), p. 298. 



