POLYPODIACEiE. 15 



with an obtusely angular, stout, erect, smooth stipes, and main rha- 

 chis; the breadth of the frond at base about 18 inches, contracting 

 very gradually upwards for the first 2 or 3 feet, then terminating in 

 an acuminate point, and bipinnate. Pinnce about 2 inches apart, 

 opposite or somewhat alternate, sessile and horizontal, sometimes a little 

 undulate, linear, and attenuating into a lobate serrate point, pinnate at 

 the base. Pinnules numerous, someicfoat alternate, about an inch in 

 length, oblong, obtuse, coarsely crenate-dentate, the surface punctulate. 

 Partial rhachis of a pale straw-colour, setose on the upper side; t7ie under 

 side, together with that of the costa, furnished with a pale short pubes- 

 cence. Sori either irregular or biserial. 



In habit, this bears a strong resemblance to the P. Keraudrenianum 

 of Gaudichaud ; but is very distinct in the form and size of the divi- 

 sions of its fronds. 



Plate 3. — Fig. 1. Section of frond, of the natural size. a. Under 

 side of a portion of a fertile pinnule, b. Hairs from the veins on the 

 under surface, c, c. Sporangia. The analyses magnified. 



25. Polypodium Keraudrenianum, Gaud, 



Polypodmm Keraudrenianum, G-aud. Bot. Freyc. Voy. p. 362, t. 7. 



Hab. Sandwich Islands : on the margins of forests, among bushes 

 and low trees. 



The fronds of this species, which are very long and slender, rise to 

 the height of 12 to 15 feet. They are sustained in a more or less 

 erect position by the reflected points of the pinnse, which bend over 

 and around the branches and stems of neighbouring plants. Another 

 peculiarity in this Fern is, that the fronds continue to grow at the 

 point, while at the same time, for a distance of 2 to 3 feet from the 

 base upwards, they are fully developed, and bearing ripe sori. 



26. Polypodium crinale, Book. & Am. 

 P. co3spitosum, stipitibus crassis sulcatis dense jpaleaceis * frondibus bipin- 



