AN ENUMERATION 



OF 



CULTIVATED FERNS. 



Oedee I.-FILICES. 



Fronds circinately unfolding, uniform and leafy, bearing 

 sporangia on their under side or margin (rarely on both sides); 

 or of two forms, one leafy and sterile, the other wholly, or somo 

 portion of its segments more or less contracted and fertile. 

 Sporangia membraneous, one-celled, free, furnished with a 

 vertical, horizontal, or oblique articulated elastic ring. 



Sub-Obdee I— POLYPODIACEJE. 



Sporangia globose or oval, unilocular, pedicellate or sessile, 

 membraneous, furnished with a vertical ring, and opening at a 

 right angle to the direction of the ring. 



Division I. — Eremobrya. 



Fronds in vernation lateral, solitary, attached to the axia 

 (rhizome) by a special articulation. 



* Sori indusiate. 



Tiube I.- OLEANDRE^!. 



Sori round, medial. Indusiwn lateral, interiorly attached or 

 Bometimes central, plane. 



