FILICIN^. 39 



specimens placed together under Ruffordia Gopperti (Dunk.), 

 as shown in Pis. III.-V., will be regarded by some as obviously- 

 distinct ; such, indeed, they may prove to be, but at present I am 

 unable to draw any line between the various types which seem 

 to pass gradually one into another without any appreciable break. 

 To class such leaves together among living ferns would not be 

 considered an unwarranted step in the case of certain species ; if, 

 therefore, such a course is adopted in dealing with fossil ferns 

 there can be no very serious argument advanced against it. 



In a recent volume of Engler's "Botanische Jahrbiicher," we 

 have an interesting account by Eaciborski of a Mesozoic fern flora 

 from Jurassic rocks in the neighbourhood of Cracow.' He has made 

 good use of the specimens of fern sporophylls at his disposal, and 

 from the character of the sori and sporangia he has been able to 

 refer many species to their natural position. The genus Klukia is 

 proposed by this writer for the reception of some widely-spread 

 species which possess sporangia of the same type as those of the 

 recent ScMzaee<B. Such a resemblance to Schizaeea was first pointed 

 out by Bunbury '' in Peoopteris exilis, Phill., from the Yorkshire 

 coast; this species he referred to a position near to Anemia and 

 Mohria. Researches such as this are of the greatest value, and by 

 instituting new names like the one proposed by Raciborski, we are 

 removing the plants from a purely artificial designation to a place 

 in the same category as recent ferns, where the generic and specific 

 titles are professedly based on accepted and trustworthy characters. 

 In the following descriptions of "Wealden Filices, the acquisition of 

 a considerable amount of fresh material, thanks mainly to the 

 labours of Mr. Eufford, has enabled us to arrive at certain con- 

 clusions as to the systematic position of plants hitherto known 

 under provisional names. The transference of Sphenopteris 

 Mantdli, Brong., to Onychiopsis MantelK (Brong.), is an instance 

 of this ; and in the case of the Wealden species, Sphenopteris 

 Gopperti, Dunk., there is evidence at hand which renders 

 the employment of a new generic designation an advisable 

 step. In both these instances I have mentioned, the change 

 of name, and the reference to certain families of ferns, are based 



- Bot. Jahrb. vol. liii. p. 1, 1891. 



* Quart. Journ. Geol. Soo. vol. vii. 1851, p. 188, pi. xiii. figs. 5« and 6b. 

 An examination of Bunbury's specimen (Botanical Museum, Cambridge), enables 

 me to confirm the reference to Schizacete. 



