J.SMITH ON THE GENERA OF FERNS. 181 



these two characters are not always constant, for both modes 

 of attachment are often found upon the same frond; conse- 

 quently the form of the indusium is not to be wholly depended 

 upon. 



In at least four genera containing but few species, the in- 

 dusium is attached all round the base of the receptacle, and 

 include the sporangia, forming a more or less perfect cup, 

 analogous to the tribe Cyathece, but wanting the elevated 

 receptacle that particularly characterize that tribe; for the 

 pediciliate sori of Sphtsropteris, (which I place in ^ispidiece), 

 cannot in my opinion be viewed as an elevated receptacle, 

 even although the form of the indusia of the genera here 

 alluded to would warrant their being placed in Cyathece ; but 

 on viewing their habit and characters in every other respect, 

 I do not hesitate in placing them in this tribe. Aspidiece 

 contains probably above 200 described species, and is readily 

 distinguished from Aspleniece by the sori being round, with 

 the indusium (when lateral, as in a\\ AspleniecE) attached across 

 the venule, and not longitudinally in the direction of the ven- 

 ules as in Aspleniets. From the following tribe Dicksouiece, it 

 is distinguished by the indusium of that tribe always conniv- 

 ing with the altered indusiiform margin. 



Sect. I. SYMPLOPHLEBIEiE. 



Venation variously anastomose, or reticulated. 



77, Matonia, B. Br. 



Veins forked ; vemdes fertile anastomosing, sterile ones di- 

 rect and hee ; sporangia definitely disposed in a simple series 

 round a special receptacle, produced on the axes of conflu- 

 ence of numerous veinlets, furnished with an orbicular, in- 

 flated central attached indusium, constituting globose sori. 

 *' Rhizoma creeping, 6 to Sfeet high." Fronds cordate-flahel- 

 late, multipartite, segments uniform, linear, equally pinnatifid, 

 rigid, glaucous,from 1 to 2 feet in length, lacinicR about 1 inch in 

 length, linear-lanceolate, obtuse, costate, lower venules anasto- 

 mosing, forming 2 to 1 soriferous points parallel with the mid' 



