64 



BRITISH EOCENE FLORA. 



renders it more probable that it may belong to Struthiopsis, a section of Onoclea, with 

 similar venation, in which the fertile fronds are separate and of a kind not easily 

 preserved. The venation is also met with in Acrodichum and Nephrodium, one species 

 of the latter, N. omboinense, resembling the fossil almost as much as the Goniopteris 

 mentioned. 



8. GoNioPTERis STIRIACA, TJnger. (Page 39.) 



This and a number of similar species, most of which need not have been separated, 

 are distinguished by their pinnatifid or distinctly crenate pinna3, and by curved, instead, 

 as in the former species, of angular secondary veins. In the Bovey and some other 

 instances all the secondary veins anastomose, in others fewer, or the lower pair only. 

 The attachment of the pinnse to the rachis and the sori to the pinna is remarkably con- 

 stant, even in small fragments. In England it has only been collected at Bovey Tracey,^ 

 but in Switzerland, Austria, Italy, Erance, and America, numerous specimens have been 

 found and sometimes described as distinct species. On the other hand, it may be doubted 

 whether the specimens from the extreme north, as Cape Lyell and Atanekerdluk, are 

 really the same. 



The venation is of a type common to many genera among Eerns, and, like that of 

 G. Bunhurii, occurs in Acrostichum and Nephrodium^ but in the present case the 

 arrangement of the sori lends support to our determination. Unger considered that it 

 most resembled G. jjroliferum, but there are species which even more nearly approach it, 

 and the form and venation recur in several genera. 



9. Phymatodes polypodioides, Ett. 8f Gard. (Page 29, under genus Podoloma, Eft.) 



No Polypodium with reticulated venation has previously been met with fossil in such 

 excellent preservation. It is strictly confined at Bournemouth to a local bed, in which 

 the pinnse abound, lying flat and in layers, having been articulated and deciduous. They 

 so resemble dicotyledonous leaves as to have induced some scepticism with regard to 

 their classification, but comparison with existing Eerns, especially with those indigenous 

 to Tropical America, such as P. geminatum, P. stigmaticum, P. Igcopodioides, and 

 P. persieariafoliiim, places its position beyond all reasonable doubt, and also shows the 

 genus Podoloma to be unnecessary. It appeared especially remarkable from the fact 

 that the reticulations converge round the sori (PI. XII, fig. 10), but an examination 



1 The same species may be represented at Bournemouth by the pinna described as Phegopteris pra- 

 cuspidata. 



I 



