186 J. SMITH ON THE GENERA OF FERNS. 



Presl has constituted a genus (Ehagiopteris,) on two other 

 presumed species of Onoclea; but it appears to me that there 

 are no such species, and that the specimens upon which he 

 characterized his genus have (by mistake,) consisted of the 

 fertile frond of Onoclea sensibilis and the sterile frond of 

 some other fern, an instance of which I have witnessed 

 among Pursh's specimens of Onoclea in the herbarium of 

 Mr Lambert. 



83. Cyrtomium, Presl. 

 (Aspidii sp. Sw. Wall.) 



Veins pinnate; the lower exterior venule free and fertilcj 

 the other angularly anastomosing, and producing on their 

 exterior sides or angular junctions 1, 2, or 3 excurrent fer- 

 tile free veinlets ; sporangia medial ; sori round ; indusiura 

 orbicular, central. 



Fronds pinnate ; pinnce ohlong -acuminate falcate, ohlique 

 or lohed at their base, margin entire or spinulous ; sori nu- 

 m erous, transversely -tnultiserial. 



Species. 1. C. falcatum, {Sw.) 2. C. caryotideum, {Wall.) 

 lllust. Hook, et Grev. Ic. Fil. t. 69. Hook. Gen. Fil. t. 49. c. 



Obs. The two species constituting this genus approach in 

 habit and texture the extensive genus Polystichum in the fol- 

 lowing section, none of the venules of which anastomose; and 

 it is evident, on viewing the habit and venation of this and 

 the two following genera, that they form a gradual transition 

 to the free venation which characterize Polystichum. The 

 character of Cyrtomium^ as respects venation and position of 

 the sori, is somewhat analogous to Goniophlehium and Cyr- 

 tophlebium in Polypodiece. 



84. Phanerophlebie^>, Presl. J. Sm. 



(Aspidii sp. Schlecht, Polypodii sp. Humh. Arablia, Presl.) 



Veins pinnately-forked ; the lower exterior or usually both 



the lower venules free and fertile, the superior ones angularly 



anastomosing and also fertile; sporangia medial; sori round; 



indtisinm orbicular, central. 



