CHARACTERS OF TRIBES AND GENERA. 135 



OBS, This genus is founded on a solitary species, a 

 native of Venezuela and Mexico, which in general habit 

 agrees with Polybotrya, but is distinguished by the venules 

 being combined, forming oblique elongated areoles. In 

 general the sterile fronds are pinnate, with nearly entire 

 pinnae ; but in cultivated plants fronds are often produced 

 with deeply laciniated pinnae, similar to the states observed 

 in Olfersia. In these specimens the veins of each of the 

 lacinse are partially thickened, and more or less united ; 

 and often towards the apex of the frond the lacinae show 

 some degree of contraction, and produce distant round 

 masses of sporangia on their apex or margin, thus showing 

 that the fertile fronds are only a highly contracted state of 

 the sterile. 



Sp. S. serratifolium, Fee Acrost., t. 43 (v v.). 



51. STENOSEMIA Presl (1836). 

 Polybotrya sp. auct. ; Acrosticlium sp. Hook. Sp. Fil. 



Vernation fasciculate, acaulose. Fronds few, erect, del- 

 toid, ternately pinnate, 6 to 18 inches long, segments 

 laciniately lobed, bulbiferous. Veins pinnate ; the lower 

 venules transversely anastomosing, forming elongated costal 

 and sub-costal areoles, the exterior venules free. Fertile 

 segments linear, rachiform, involute, nearly wholly sporangi- 

 ferous. 



Type. Polybotrya aurita, Blume. 



Illust. Hook. Gard. Ferns, t. 81 ; Moore Ind. Fil., p. 6 B. ; 

 J. Sm. Ferns, Brit, and For., fig. 41 ; Hook. Syn. Fil., 

 t. 7, fig. 60, t. u. 



OBS. This genus consists of a single species, a native of 

 the Malayan and Philippine Islands, which to a certain 

 extent in the character agrees with the following genus, 



