MAXON STUDIES OF TROPICA]. AMERICAN FERNS. 39 



Aspidium melaxochlamys Fee, Gen. Fil. 294. 1850-1852. 



A Cuban species, founded upon Linden 1805, from Monte Libano, province of San- 

 tiago (Oriente;; placed under Polystiehum by Diels (1899), the synonymy indicated 

 by Christensen. Known to the writer from the following specimens: 



Cuba: Joaephina, north of Jaguey, Yateras, province of Oriente, altitude about 

 575 meters, Maxon 4109; caverns of Thermopylae and vicinity, Monte Libano, 

 Oriente, altitude about 600 meters (the type locality), Maxon 4251. 



A very peculiar species, allied to the Mexican Dryopteris melanosticton, and properly 

 referred to Dryopteris by Kuntze (1891 J. Immature fronds show the indusia to be 

 markedly bicolorous, orbicular, and uniformly with a very narrow sinus; the center 

 is dark purplish brown, the margins abruptly paler. 

 Aspidium viscidulum Mett. Abhand. Senck. Nat. Gesell. 2: 322. 1858. 



The synonymy of this species, the type of Adenoderris, is correctly given by Chris- 

 tensen, in accordance with a paper published by the writer several years ago." The 

 relationship with Polystiehum is not a very close one. 

 Polyfodium penticu latum Sw. Prodr. 134. 1788. 



Described originally from Jamaican specimens, the continental forms smaller and 

 apparently constituting several poorly defined species. Like D. cubensis, it is in 

 technical character of indusium a Dryopteris, as shown by an ample suite of Jamaican 

 specimens. The synonymy is indicated by Christensen. 

 Duksonia apiifolia Sw. Schrad. Journ. Bot. 1800-': 91. 1801, not of later authors. 



Christensen in his Index has recently pointed out that this is the earliest name for 

 the plant usually known as Aspidium ascendens Howard (1838), both names having 

 been applied originally to Jamaican plants. The species has been well characterized 

 by Jenman and various other authors and has received at least one other specific 

 name, having been described and illustrated upon Guatemalan specimens by Captain 

 Smith in 1890 as Xephrodium duale Donn. Sm. It occurs also in Cuba. Moore (1858) 

 regarded it as a Polystiehum. in which he has been followed by Diels (1899); but how- 

 ever much it may resemble in habit certain species of Polystiehum, notably P. 

 adiantiforme, in the character of its indusium, it is technically a Dryopteris. In its 

 habit and strongly dimorphous fronds it bears the closest resemblance to various 

 Polybotrya species, the fertile fronds being mere skeletons in comparison with the 

 sterile (foliar) ones. To avoid an excessive multiplication of generic names it may 

 perhaps preferably remain under Dryopteris. but it ought at least to rank as a sub- 

 genus, for which the name Peismapodium is here proposed. The synonymy of 

 Dryopteris (Peismapodium; apiifolia (Sw.) Kuntze is given in full by Christensen. 



DESCRIPTIONS OF NEW SPECIES. 



Asplenium palmeri Maxon, sp. nov. 



Rhizome slight, 4 or 5 mm. in diameter, ascending, bearing a few thickened linear- 

 lanceolate blackish scales (1.5 to 2 mm. long) with lighter margins; fronds 4 to 8 in 

 number, cespitose, 8 to 20 cm. long (averaging about 12 cm.), spreading, commonly 

 arcuate throughout, particularly in the apical portion; stipes 1 to 2.5 cm. long, slender, 

 dull purplish black; lamina 7 to 17.5 cm. long, 9 to 18 mm. broad (averaging about 12 

 mm.), linear, 25 to 34- jugate, reduced gradually in both directions, the apex commonly 

 naked, flagelli form (1.5 to 2.5 cm.) and radicant, giving rise to a new plant by means of 

 a terminal proliferous bud; characteristic middle pinna; horizontal, G to 9 mm. long, 

 3 to 4 mm. broad, oblong, subauriculate or even subhastate, broadly and subequally 

 cuneate, the margins regularly and conspicuously serrate; lower pinnae shorter, has- 

 tate, very broadly cuneate, horizontal, the margins deeply and somewhat irregularly 

 crenate-serrate, the lowermost pinnce distant and frequently minute; sori medial, 

 about 4 or 5 pairs to the pinna, confluent with age; indusia elliptical, firm, glabrous, 

 the margin subent ire. 



« Adenoderris. a valid genua of ferns. Bot. Gaz. 39: 300-369. 1905. 



