THE JURASSIC FLORA OF SUTHERLAND. 673 



a few highly inclined secondary veins. In Onychiopsis Mantelli the pinnae have a 

 serrate lamina or, in the more deeply dissected pinnae, the ultimate segments are longer 

 and relatively narrower than in the Culgower specimens. Good examples of 0. Mantelli, 

 which Lester Ward speaks of as Onychiopsis psilotoides (Stokes and Webb # ) in 

 accordance with strict adherence to priority, are figured by ScHENK.t Velenovsky,| 

 and Heer § from Wealden localities in Germany, Bohemia, and Portugal, and by myself 

 from the Wealden of England, || also by Geyler and Yokoyama from Japan ; the same 

 type is described also from South Africa. IT Some specimens referred to Saporta's genus 

 Scleropteris bear a fairly close resemblance to Sphenopteris onychiopsoides, but in such 

 a type as Scleropteris Pomelii ** the habit is much more rigid. Comparison may also 

 be made with Scleropteris virginiana Font.tt from the Potomac of Virginia and with 

 S. distantifolia described by the same author from the Black Hills of Dakota.^ Similar 

 fern fronds are figured by Heer, Yokoyama, and other authors as species of Dicksonia, 

 but as a rule without adequate evidence in favour of the use of the generic name 

 Dicksonia : D. gracilis Heer, §§ from Siberia and Japan, especially resembles the 

 Culgower plant. A fragment figured by Nathorst as Sphenopteris sp. |||| from the 

 Upper Jurassic of Spitzbergen may be compared with S. onychiopsoides. In the first 

 volume of my Wealden Flora it was suggested that Pecopteris Geinitzii,^ as figured by 

 Schenk from the Wealden of North Germany, might be identical with the plant which 

 I called Nathorstia valdensis and afterwards changed to Leckenbya valdensis on account 

 of the previous use of the genus Nathorstia. *** A more recent examination of the 

 specimens convinces me that this comparison is incorrect. Schenk's specimen is, I 

 believe, identical with the Culgower species, but as the specific name Geinitzii has 

 already been used in connection with Sphenopteris the new name onychiopsoides is 

 adopted. The non-committal name Sphenopteris is preferred to Onychiopsis, as 

 we have no evidence as to the nature of the fertile pinnules of the Scotch fern. 



Tseniopteris, Brongniart. 



Tseniopteris sp. (PI. II. figs. 39, 39A.) 



The genus Tseniopteris is represented by a solitary specimen in the Culgower flora 

 which is too incomplete to be assigned to a species. The fragment shows part of one 

 side of a lamina characterised by curved oblique veins forked at the base and in other 

 parts of their course (fig. 39A, PI. II.). In the Jurassic T. vittata Brongn. the veins 

 are more crowded and pursue a more direct course to the edge of the lamina. 

 Specimens figured by Yokoyama as T. cf. Richthofeni Schenk ttt from Japan bear a 

 close resemblance to that shown in fig. 39. 



* Ward (05). t Schenk (71) % Velenovsky (88). 



§ Heer (81). || Seward (94) ; see referenees to literature, p. 41. IT Seward (03). 



** Saporta (73), pi. xlvii. tt Fontaine (89), pi. xxviii. } { Ward (99). 



§§ Heer (77) (78). || || Nathorst (97), p. 49. 1T1T Seward (94), p. 145. 



*** Seward (95), p. 225. ttt Yokoyama (89), pi. iii. 



