l!'l l'"'. II.'"..' (I.ASSri irATIO.N OF FOSSIL I'LANTS. 377 



\'2 and lo, pp. r)7 and ')!!, res])., in my ^lesu/oic Flora of Gra- 

 liani Land, the illustrations given hy Hkkii (I. c; 1^1. 14; Pi. 

 1'), tigs. 1 — 10) and es])peially the photographs in I'l. 10. figs, 

 l-fi. of thr present paper may he regarded as showing the typi- 

 <al shape of the pinna-hase (»f the group in (lutstion. A (-(^m- 

 parison of these illustrations with those given in 1*1. !• of spe- 

 eirs of Ffiloplnillnm cannot fail to show the diffei'ence. It is 

 true that there may he many cases in which the distinctive 

 characters cannot he discerned <in account of tlie })reservation, 

 and also that intermediate forms exist; hut the same will be 

 found to be the case with every other classification of these 

 fronds. In a fairly large material of Vtilophylhnn pcctinoi- 

 <lrs from Whitby in Yorkshire I have found the generic charac- 

 ter - in Feistmantel's sense — to be present in all well 

 preserved specimens. It is possible that in the larger collec- 

 tions in English museums there may be transitional forms; 

 l)ut as the proportion may be taken to be the same, these 

 cannot l)e very numerous. — The same remark applies to the 

 si)ecimens of F. pecten from the Middle Estuarine series and 

 probably to the larger number of the forms referred, in Pro- 

 fes.sor Seward's Jurassic Flora of the Yorkshire Coast, to 

 WiUiamsoiid pecten, not, however, to Otozandtes (ioldiei Bkun., 

 (as figured l)y Saporta 1N75), 0. Hislojii Feistm.. 0. aufinsti- 

 foiius Heer, etc., which arie regarded in the same work as 

 synonyms of Williaiusonia pecte}t, but which I should prefer 

 to retain in the genus Otozamites. 



If forms like my Antarctic species of Zamites and the 

 Greenland fronds described by Heer under that name are re- 

 ferred to J*ftl()2)hi/lln)ii, the chief character of that genus as 

 defined by Fel^^tmaxtel could no longer l)e upheld. Instead 

 there would li<* included in the same genus forms with two 

 tvjjes of pinna-bases: the symmetrical base with slightly 

 rounded corners of m}' Suhzaiitifes-gvoui) and the asymmetri- 

 cal decurrent base of VtiloplujllmH in Feistmantel'.>< sense. 

 It would be difficult to find any sufficient generic character 



