POLYPODIACE.E. 269 



ribus; indusio orbiculari inflate basi in laciniam brevem immerso 

 bipartite, valvis integerrimis ; receptaculo brevi apice capitate. 



Hab. Mountain forests of Tahiti, Society Islands: on rocks and 

 trunks of trees. 



Rootstock very long and creeping. Stipes smooth, terete at the 

 base but margined above. Fronds erect, quite elastic, drying of a dull 

 brown colour, of an oblong-lanceolate form, acuminate, tripinnatifid, 

 and frequently with a partially caudate-acuminate point, from 8 to 

 10 inches in length and 4 to 6 inches broad; all the divisions rather 

 crowded ; the primary ones alternate, ascending, somewhat imbricated 

 and pointing upwards; the secondary ones broad-ovate, obtuse, and 

 divided in a palmated manner; the lacinice narrow-linear, obtuse, 

 simple or bifid. Sori rather few, confined to the upper half of the 

 frond, seated on short lateral lacinice (supra-axillary). Indusium orbi- 

 cular, inflated, entire, the base slightly immersed, the two valves divided 

 almost to the base, and enclosing the short capitate receptacle. 



A very handsome species, allied to H. dilatatum, Swartz, in the 

 tripinnatifid fronds and the subpalmate secondary divisions: but 

 differing in the more crowded and ascending primary divisions, which 

 are not at all translucent; also in the supra-axillary sori and the 

 anomalous capitate receptacle. 



Plate 37. Fig. 3. Frond, of the natural size. 3 a. Portion of the 



same. 3 b. A single sorus, with the indusium removed. 3 c. A 

 sporangium. — More or less magnified. 



15. Hymenophyllum recurvum, Gaud, 



Hymenophyllum recurvum, Gaud. Bot. Freyc. Voy. p. 376; Hook. & Am. Bot. 

 Beech. Voy. p. 109; Hook. Spec. Fil. 1, p. 104, t. 37, C. 



Hab. Sandwich Islands ; where it is a very common Fern, on the 

 trunks of trees. 



This is the most variable species of the genus that has come under 



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