17 



2-^—9 cm. broad, often rather firmly herbaceous, glabrous ; rachis slender, 

 weak, [)a!e when dried but sometimes purpurascent, often fibrilloso-squamose 

 at the base of pinuEe ; pinnte numerous, 15-28 on each side, usually alter- 

 nate, sessile, patent and often approximate, but the inferior ones apart 

 and more or less reflexed and gradually diminished in size, narrowly 

 deltoid-lanceolate and usually acuminate, but narrowly deltoid and acute or 

 obtuse in the inferior ones, truncate or subtruncate at the base, pinnatifid 

 with closed sinuses, attaining about 4i cm. long in the middle ones ; lobes 

 elliptical or ova to-oval, rounded or obtuse at the apex, irregularly pauci- 

 crenate or pauci-serrate, the upper basal one largest and oblong ; venation 

 conspicuous, often slightly elevated beneath when dried ; veins erect-patent, 

 flexuous, pinnate ; venules louse, erect-patent, simple or sometimes furcate. 

 Sori proportionally large, 1-5 (their lowest ones forming a row on each 

 side of the midrib apart from it) to each lobe of the pinnae, but more 

 numerous in the upper basal lobe, dorsal on the upper portion of the 

 venules, elevated, hippocrepiform or reniform or elliptical ; indusium thinly 

 numbranaceous, entire or suberose on the margin, persistent. Sporangia 

 obovato-oval, the pedicel about as long as the case ; spore elliptical, rugose, 

 yellowish. 



Nom. Jap. Iwa-inuioarahi (nov.). 



Hah. Prov. Shimotsuke : Mt. Nikko {T. Makino ! Aug. 29, 1901), 

 Between Ashio and Mt. Koshin {T. Makino ! Sept. 11, 1901). 



This species has undoubtedly an affinity to Atliyrium yokoscence (Franch. 

 et Sav.) Christ, though simpler in form and smaller in size. As far as 

 I know, the habitat is restricted to rocky place of mountains, found 

 rarely. 



Athyrium yokoscence (Franch. et Sav.) Christ in Bull. Herb. 

 BoL?s. IV. (1896) p. 668. 



Asplenium yokoscence Franch. et Sav. Enum. PI. Jap. II. (1879) pp 

 225, 622. 



Caudex short, erect or ascending, thickly covered with castaneous bases 

 of old stipes. Sti[)es ctespitose, erect, slender, clothed with scales towards 

 the base, pale-stramineous, attaining about 28 cm. long, but sometimes 

 short and 3| cm. long ; scales lanceolate to linear, acuminate, entire, 

 ■firmcly or thinly membranaceous, ferruginous and concolorous, but often 

 castaneous excepting the margin. Frond oblong or oblong-lanceolate, 



