MAMi.X- -STUDIES OF TROPICAL AMERICAN FERNS. 485 



Pessopteris Underw. & Maxon, Qom. nov. a 



Inaxetum Schott, Gen. Fil. pi. t. 1834, Not Anaxeton Gaert. Fruct. 2: 100. 



l»l. 166. f. I". L791. 

 Pleuridium Fee, Gen. Til. l:?:;. 1850 52. Nol Pleuridiuni Bridel, Mant. Muse. 

 10. 181*9. 



The type mid sole species is : 



Pessopteris crassifolia ( L. i CJnderw. & Maxon. 



Poly podium crassifolium L. Sp. PI. 1083. IT.".:;. 



Inaxetum crassifolium Schott, Gen. Fil. /</. /. L834. 



Pleuridium crassifolium Fee, Gen. Fil. 274. L850 52. 



Generally distributed throughout tropical America, and subjecl i" consider- 

 able variation, several forms having been described ;is distinct species. 



THE CUBAN SPECIES OF ADIANTOPSIS. 



Three species <>!' A^diantopsis have been known hitherto from 

 Cuba. These are: 



Adiantopsis radiata (L.) Fee, Gen. Fil. 1 15. L850 52. 



Adiantum r<i<n<thi„i L. Sp. PI. 1094. IT-".:;. 



Not uncommon through tropical America generally. 

 Adiantopsis pedata (Hook.) Moore, Intl. Fil. 18 L857. 



Hypolepis pedata Hook. Sp. Fil. 2: TA. id. 92. A. L852. 



Known definitely from Jamaica and Cuba; accredited also to Peru, 

 Adiantopsis paupercula (Kunze) Fee, (ion. Fil. 145. 1850 •"•-'. 



Adiantum pauperculum Kunze, Farnkr. 2: 65. pi. 121. I s -"'". 



Known only from Cuba and Jamaica. 



To these must he added a fourth very different species: 



Adiantopsis rupicola Maxon. sp. nov. 



Plant rigid, 50 cm. high, fronds several, closely clustered upon an ascending 

 WOOdy rhizome covered with bright brown irlossy linear chaff with a dark me- 

 dian line: stipe 20 cm. long, naked, shining, purplish brown; lamina 30 cm. 

 long, 1<» to 12 cm. lu-oad. deltoid-lanceolate, coriaceous, glabrous excepi for a 

 few whitish club-shaped glandular hairs on the under surface, bipinnate or. as 

 to mature specimens, subtripinnate in the lower half: pinnae subopposite, f« >r 

 the most pari unequally deltoid-lanceolate with subhastate entire apices; basal 

 pinna' about 7 cm. long, '-\ cm. broad at base, unequally triangular, the two 

 lowest pairs of pinnules pinnate, the inferior twice as long as the superior; 

 second and third pairs of pinna? narrower, of similar but less pronounced 

 basiscopic development, only the basal pair of pinnules again pinnate: succeed- 

 ing pinnae pinnate only (except for the pinnatifid basal pinnule), gradually 

 pinnatifid, finally auriculate and entire, the uppermost produced to form the 

 somewhat attenuate apex of the frond: pinnules at right angles to th< 

 ondary rachis, characteristic ones broadly elliptical to ovate, obtuse, somewhal 

 excised at the base below, auriculate: sori numerous, marginal, terminal on 

 the veins: indusia single < or rarely double), spaced about half their width or 

 less, whitish, oblong to subreniform, reflexed at maturity to the plane of the 

 frond. 



Type in the U. s. National Herbarium, no. 372124, collected by William 

 rahner and J. II. Riley ino. 242) in crevices of partially shaded limestone 



"From Greek irtaaov. a draughtboard (checkerboard) and nrtpis. a kind of 

 fern, in modern use any fern. 



