EOCENE EERNS. 



57 



of plant, we may hope to trace its life-history. Thus, it can scarcely be doubted that we 

 are already in possession of a series of modifications of the species of Lygodimi now 

 represented by L. palmatum, a form so distinct at the present day that it is the only type 

 of one section of the genus, and the history of which, traced back to pre-Eocene times, is 

 marked by slight but frequent modifications in the form of the barren fronds, while the 

 fertile fronds have remained almost unchanged.* On the other hand we see, for example, 

 that hardly any modification has taken place in CUrysodimi aureum, and none is 

 perceptible in Osmunda Javanica since Eocene times. 



TABLE OF THE MORE DISTINCTIVE OF THE BRITISH EOCENE FERNS, WITH THEIR 

 NEAREST FOSSIL AND EXISTING ALLIES, ARRANGED ACCORDING TO SIR W. 

 HOOKER'S CLASSIFICATION. 



Sub-order I. 

 GLEICHENIACEiE. 

 Genus Gleichenia. 

 f G. Hantonensis 



Sub-order II. 

 POLYPODIACEiE. 

 Tribe VI, Pteride/E. 

 Genus Adiantum. 

 A. apalophyllum 



Sub-genus Hewardia. 



fH. regia ..... 



Genus Pferis. 

 P. eocenica. (P. Gaudini, Heer, 

 Osmunda (?) eocenica, Sap., 



&c.) 



P.Bournensis. (P. Aquensis, Sap., 

 P. Qiningensis, Ung., and 

 very many others) 

 Tnbe VII, BLECHNEiE. 

 Genus Woodwardia. 



* W. RcEssneriana, Ung. (This, A 



although not a British fossil, / 

 is tabulated in place of the t 

 more doubtful W. venosa) . J 



Tribe XI, Poltpodi/e. 



Sub-genus Goniopteris. 



* G.Bunburyi. (G. polypodioides, ) 



G. (Eningense, A. Braun,&c.) j 



In Europe. 



o 



Range of nearest existing representative 

 (for details, consult Hooker's ' Synopsis 

 Filicum.') 



f G. dichotoma. Tropics of Eastern 

 1^ and Western hemispheres. 



(A. capillus-veneris. Sub-tropical and 

 < S. temperate regions of Eastern 

 ( and Western hemispheres. 

 I H. Wilsoni, Tropics of Western 

 hemisphere. 



( P. cretica. Sub-tropical and S. tem- 

 ^ perate regions of Eastern and 

 ( Western hemispheres. 

 ( P. aquilina, Northern and temperate 

 J to tropical regions of Eastern and 

 (_ Western hemispheres. 



f W. radicans, sub-tropics, Eastern 

 \ and Western hemisphere. 



G. diversifolium. Tropics of Western 

 liemisphere. 



* We are indebted to Count Saporta for information concerning the fertile fronds. 



