A NEW SPLEENWORT FROM CHINA. 
By Wittram R. Maxon. 
The Chinese fern here described as new was detected several years 
ago in the course of a study of Asplenium trichomanes and its allies. 
Its relationship is discussed below. 
Asplenium microtum Maxon, sp. nov. PLATE LX. 
Rhizome suberect, 5 to 7 mm. in diameter, thickly beset with rigid linear- 
lanceolate dark brownish scales about 2 mm. in length; fronds few (4 to 8), 
cespitose, divergent, subarcuate, 15 to 20 cm. long; stipes dull purplish black, 
flexuose, 2 to 3 em. long; lamina 12 to 17 em. long, 11 to 13.5 mm. broad, 
linear: pinnze subcoriaceous, deciduous, 25 to 32-jugate, mostly opposite or sub- 
opposite, approximate or their width apart, gradually reduced both above and 
below; characteristic middle pinnre 6 to 7 mm. long, sessile, subrhombic to 
oblong, the base appearing (in dried specimens) narrowly long-cuneate, some- 
what excised below, auriculate above, the apex rounded, the margins lightly 
crenate-sinuate, revolute in drying; lower pinnze shorter, broader, decidedly 
auriculate, somewhat refiexed, easily deciduous, the lowermost 2 or 3 distant, 
greatly reduced, subalternate or alternate, a minute, persistent bud with con- 
spicuous chaff borne commonly at the base of the last or next to the last; 
stipe and rachis narrowly alate, the wing conspicuously erose-dentate or even 
serrate; sori medial, linear-oblong, usually 6 (in 3 pairs) or 7, the odd one 
in the upper row; indusia ample, firm, glabrous, the margin lightly sinuate ; 
spores dark brown, ovoid, somewhat cristate, conspicuously alate and reticulate. 
Type in the U. S. National Herbarium, no. 455004; from Mengtse, Yunnan, 
China, A. Henry (no. 10344). The same number in the herbarium of the 
Missouri Botanical Garden bears the additional data: “s, w. mts., alt. 6000 ft.” 
Mentioned by Christ,* some time ago, under the name Asplenium trichomanes, 
as a form ‘“ with distant strongly auriculate pinne.” A. microtum is, appar- 
ently, a near relative of A. trichomanes; but from this, which, in a typical 
state at least, seems to be confined to North America and Europe, it differs 
very noticeably in (1) its subcoriaceous texture, (2) its auriculate pinne, these 
narrowly cuneate at the base (really less so than appears in the dried plants), 
(3) its strongly revolute and lightly crenate-sinuate murgins, and (4) the 
presence of a minute but very chaffy bud upon the rachis, near its base. 
This last is a character noted hitherto, in the group of Asplenium trichomanes, 
only in A. platyneuron and A. monanthes; in the former very rarely; in the 
latter commonly, sometimes near the base, but often in the apical portion. 
A Mexican species of this group, as yet undescribed, has the fronds radicant 
and proliferous at the very apex. 
For the drawing herewith reproduced the writer is indebted to Dr. H. D. 
House, of the Biltmore Forest School. 
EXPLANATION OF PLATE LX,—a, Plant; b, segment of a frond. a, Natural size; b, 
seale 2. 
“Bull. Herb. Boiss. 6: 960. 1898. 
411 
