180 J. SMITH ON THE GENERA OF FERNS. 



Wallichian herbarium at the Linnsean Society. The genus 

 therefore appeared to me a very doubtful one, but it is 

 now explained by the possession of ample specimens brought 

 from the Philippines by H. Cuming, Esq., which specimens 

 clearly prove that Nephrodium BanksitE/olium, tind N. Bro- 

 melicBfolium of Presl, and Asplenium auremn of Blume, are 

 one and the same, and happeh to be constituted from barren 

 portions of the frond of Osmunda Javanica ! 



Tribe V. Aspidie^. J. Sm. 



Son round, rarely oblong, intramarginal, furnished with a 

 special indusmm, which is either orbicular and produced from 

 the centre (central), or reniform or cucullate, and produced 

 from the interior side of the sporangiferous receptacle {late- 

 rat), or sometimes attached wholly round the receptacle and 

 including the sporangia, {Calyciform.) 



Ohs. This extensive tribe may be viewed as composed of 

 species analogous in habit and vascular structure to those 

 genera of the tribe Polypodieee, which have round sori ; but 

 Aspidiece differs by each sorus being furnished with a special 

 indusium, which is often very fugacious, or so small as to 

 become soon obliterated by the increasing size of the sporan- 

 gia ; and therefore in such cases it becomes difficult to deter- 

 mine in which tribe the species should be placed, and this 

 can only be satisfactorily determined, by the examination of 

 the sori in the early stage of their growth. From my own 

 observation, it appears probable that there are many species 

 described as belonging to PolypodiecE, that are true Aspidiece. 

 Therefore, setting aside the presence of the indusium as the 

 only mark of distinction between the two tribes, the whole of 

 Aspidie(B would naturally associate with Polypodie^s ; but as 

 the latter tribe is already extensive, it will be advisable to 

 allow the presence of the indusium to characterize a separate 

 tribe, consisting of genera whose differences are shown by 

 the several modifications of venation, position of the sori, and 

 form of the indusium, which latter organ is in the greater 

 mass of the species either centrally or laterally attached. But 



