658 ME. J. STARKIE GARDNER ON EOCENE FERNS FROM 



Gleichenia, species indeterminable. (Plate XXVI. figs. 10 

 & 11.) 



Eocene basalts, Ballypalady, Antrim. 



The pinnules are narrow oblong. 5 millim. wide, and cleft in 

 segments down to the midrib. These segments are somewhat 

 falcate, at an angle of 55° with the midrib and barely 2 millim. 

 across. The midrib is slender and prominent, but the rest of the 

 venation is obscure. A simple veinlet can be traced on each 

 segment, and here and there secondary veinlets diverging from 

 it; though the matrix is too coarse to retain very delicate 

 impressions. 



The remains of this fern are of the scantiest description, no 

 more than two fragments of pinnules, barely 15 millim. long, 

 being known to me. These are traced out in yellow on the deep 

 brown matrix, the outline being comparatively sharp. This 

 colouring is rarely met with ; I have only seen it in Nelumhium 

 BucMi and one or two other leaves, and I am inclined to interpret 

 its presence as an indication that the leaves possessed a thick, 

 but not coriaceous texture. 



It would be useless to attempt any generalizations upon such 

 material. There is, however, one fact too significant to be entirely 

 passed by. This is, that while innumerable examples of this type 

 are met with in the so-called Cretaceous floras with Dicotyledons 

 of America, Europe, and Greenland — such as Gleichenia Kurriana, 

 Heer, which is indistinguishable from it, and in the Heersien flora 

 Benitzia minima, Sap., and even in Eocenes of so late a date as 

 the "Woolwich beds — not the remotest trace of any fern resembling 

 it, so far as I know, has yet been brought to light from any of the 

 later Eocene beds of Europe*. Trifling as it may be, its occur- 

 rence in the Antrim basalts accords with the views I have ad- 

 vanced, and supported by, I believe, irresistible evidence, as to 

 the great antiquity of this vast basaltic formation. 



Onoclea hebridica, J. 8. Gardn. (Plate XXVJ. figs. 1-4-) 



Filicites hebridicus, Ed. Forbes, Quart. Journ. Geol. Soc. vol. vii. p. 103, 

 pi. 2. fig. 2 (1851). 



Eocene basalts. Isle of Mull. 



There are no known characters by which this fern can be defi- 

 nitely distinguished from the living Onoclea sensibilis. It is a 



* I have since ascertained that it reappears, possibly after an enormous 

 interval, in the Oligocene of Gurnet Bay, Isle of Wight. 



