152 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
between 2,700 and 3,300 meters, are figured in plate 1, figures h, i. Similar specimens 
from the Volcano Barba, Costa Rica (Pittier 1937), shown in plate 1, figure k, were 
regarded by Bommer as a valid species, Asplenium viridissimum, and were described 
by Christ as A. trichomanes var. viridissimum, These plants of the high mountains 
of Guatemala and Costa Rica represent in most respects the highest development of 
the species. Many of the individuals are more than a meter tall, the fronds usually 
numerous and closely imbricate upon a stoutish suberect rhizome, the rachises stout 
(from 1.5 to2.5mm. in diameter) and strongly winged upon the upperside. The pinne 
are numerous (60 to 80 pairs), the middle ones mostly oblong to narrowly oblong from 
a strongly inequilateral often narrowly cuneate base, strongly auriculate above, the 
lower side evenly excised about half the distance to the rounded or often subspatulate 
apex. The margins vary from crenate to lightly crenate-serrate, according to the 
fertility of the pinnz. The sori are 4 to 6 pairs in number, oblique, crowded, and 
borne mainly in pairs throughout, excepting only the auricle which bears none, or 
rarely more than one sorus. The indusia are firm, whitish, even-margined, and per- 
sistent, relatively narrower than in A. castaneum, and at maturity are mostly concealed 
by the masses of dark brown sporangia, which indeed commonly suffuse the whole 
under surface of the pinne, Nearly all the fronds are minutely viviparous near the 
apex, but no buds have been noted upon the stipe or lower part of the rachis, as is com- 
mon in ordinary forms of A. monanthes. . 
This form is a striking one, differing very materially from most conditions of A, 
monanthes, and may represent a valid species. It is nearest to the form described as 
A, galeottii, but no true intermediates have been seen. In view of the wide extent 
of variation existing among the forms which are known positively to belong to A. 
monanthes, however, it scarcely scems desirable to recognize as distinct this Costa 
Rican and Guatemalan plant, which is only a little more extreme than several other 
phases. No species retaining the common characters of this group could appear to 
be more polymorphic than A. monanthes,; and it is possible that a further investiga- 
tion may show not only ‘‘A. polyphyllum” but other of the forms here enumerated 
and figured to be improperly associated under a single species. The various phases 
or races are, however, closely allied among themselves and do not merge into any of 
the species separately listed; so that a future subdivision of A. monanthes as here 
treated need not involve a realignment of the other species. 
EXPLANATION OF PLATE 1.—Various forms of Asplenium monanthes L.: a, specimen from Natal, Bu- 
chanon,; b, Mount West, Natal, alt. 960 meters, Schlechter 6821; c, Madagascar, Hildebrandt 3591; d, Volcan 
de Agua, Guatemala, alt. 2,700 to 3,000 meters, Mazon 3739; e, Teziutlan, Puebla, Mexico, Orcutt 3987; 
7, Eslaba, Federal District, Mexico, alt. 2,350 meters, Pringle 8754; g, near Cima, State of Mexico, Rose & 
Painter 7204; h, Volcan de Agua, Guatemala, alt. 2,700 to 3,000 meters, Mazon 3733; i, same locality, Maron 
3732; k, Volcan de Barba, Costa Rica, alt. 2756 meters, Pittier 1937. All are shown at natural size. 
18. Asplenium melanorachis C, Chr. Ind. Fil. 121. 1905. 
Asplenium nigricans D.C. Eaton, Proc. Amer. Acad. 8: 619. 1873, not Kunze, 1834. 
TyPE LocaLiry: Chiapas, Mexico, on the trunks of large trees, in the borders of for- 
ests (Ghiesbreght 377). 
DistRrBuTIoN: Known only from the original collection. 
This species was well characterized by Eaton. Its relationship is discussed briefly 
under the following new species: 
19. Asplenium kellermanii Maxon, sp. nov. 
Fronds several, about 50 cm. long, ascending; rhizome erect or suberect, stoutish, 
obscurely paleaceous, the scales lance-attenuate, opaque, 1.5 to 2 mm. long; stipes 
stout (about 1.5 mm. in diameter), dark reddish brown, lustrous, nearly terete, 25 to 
30 cm. long; lamina narrowly oblong, about 25 cm. long, 5 to 9 cm. broad, simply 
pinnate, the rachis similar to the stipe, but the upper surface sulcate, narrowly alate; 
pinne 7 or 8 pairs, opposite or subopposite, sessile, subequal, the upper ones scarcely 
