FLORAS OF THE PAST. 467 



The most striking fact revealed by a general review of 

 the Wealden flora of England, Germany, and most other 

 regions is the absence of any genera which can reasonably 

 be referred to that great class of flowering plants which 

 constitutes so large a proportion of present-day vegetation. 

 It is true that certain fossil angiospermous leaves have been 

 described by Fontaine l and Lester Ward 2 from the lower 

 members of the Potomac formation which contain plants of 

 a distinct Wealden facies, and by the late Marquis of 

 Saporta 3 from rocks on a corresponding horizon in Portugal. 

 The published drawings of some of these so-called archetypal 

 Angiosperms are highly suggestive of fern leaves with 

 reticulate venation ; and while admitting the possibility that 

 some few fossil leaves from true Wealden beds may be those 

 of dicotyledonous trees, I believe it would be too rash 

 a statement to make that we have so far discovered un- 

 doubted Angiosperms in the Wealden flora. 



In connection with this question of the first appearance 

 of angiospermous leaves, I may mention that there are two 

 fairly clearly preserved leaf-impressions, which appear to 

 be those of Dicotyledons, in the British Museum collection 

 of fossil plants from the Stonesfield slate of Oxfordshire. 

 The plants from this lower horizon (Great Oolite) are now 

 being revised with a view to a comparative treatment of the 

 Stonesfield flora. 



As regards the ferns of Wealden age, the absence of 

 any species which afford evidence of Marattiaceous affinities 

 is a point of some interest. In the Palaeozoic vegetation the 

 small tropical family of the Marattiaceae appears to have 

 been abundantly represented, but in the Mesozoic epoch, at 

 least in the more recent formations, this division of the 

 Filicineae occupies a position much more in accordance with 

 that which it holds to-day. A small fragment of a sterile 

 pinna from Portugal has been referred by Saporta to the 

 genus Marattia? but it is difficult to understand on what 

 grounds the name has been adopted. Another fact which 

 is illustrated by the Wealden flora, and in a still more 



1 Fontaine. 2 Ward (3). 3 Saporta. 



4 Ibid., p. 83, pi. xvi., fig. 14. 



