rOSSIL FLORA. 75 



PLATE XXIX. 



" Trifoliate Sphenopterite." 



{Sphenopteris trifoliata, Brongniart, Hist. Veg. Foas. tab. 53, fig. 3. 

 Filicites trifoUatus, of Artis. 



Cheilanthites ; from its supposed analogy to the recent genus Cheilanthes. Goppert. 

 Trans. Academy of Bonn.) 



This is a rare species of fern from the coal shale of Yorkshire, Elsecar Colliery. It has 

 the leaf or frond tripinnate ; the pinnae, lobes, or wings, alternate with an odd one ; the leaflets 

 are ternate, with roundish, convex lobes. 



This plant has been referred to the tropical ferns, and is nearly allied to the genera Davallia, 

 or Cheilanthes ; but from the almost general absence of the organs of fructification in fossil ferns, 

 it is impossible to refer them with any certainty to living genera. It belongs to the 

 Sphenopteres, or wedge-shaped-leaf ferns, of M. Brongniart. 



A, shows the cast or matrix of the under side of the leaf; b, the upper side in relief. 



I 



