FERN FAMILY. 25 
8. Asplenium Ruta-muraria L. Wall Rue 
Spleenwort. (Fig. 53.) 
Asplenium Ruta-muraria 1. Sp. Pl. 1081. 1753. 
Rootstock short, ascending. Stipes tufted, naked, 
slender, green, 2/-3’ long; leaves ovate or deltoid-. 
ovate in outline, 2’-5’ long, glabrous, evergreen, 2-3- 
pinnate or pinnatifid above; pinnae and pinnules 
stalked; pinnules rhombic or obovate, mostly obtuse, ; 
dentate or incised, cuneate at the base; veins flabel- 
late ; sori few, linear-oblong, confluent when mature 
and covering nearly the whole pinnule, the indusium 
membranaceous and delicate. 
On limestone, Vermont to Michigan, south to Alabama 
and Missouri. Ascends to 2100 ft. in Virginia. Also in 
Europe, Asia and northern Africa. July—Sept. 
f g. Asplenium montanum Willd. Mountain 
\ 
p 
G Spleenwort. (Fig. 54.) 
Asplenium montanum Willd. Sp. Pl. 5: 342. 1810. 
Rootstock short, chaffy at the summit. Stipes 
tufted, naked, slender, blackish at the base, green 
above, 2/-3’ long; leaves ovate-lanceolate in outline, 
acuminate at the apex, rather firm, 1-2-pinnate; lower 
pinnae longest, pinnate or pinnatifid, the lobes or seg- 
ments ovate or oblong; upper pinnae less divided, 
merely toothed or incised ; veins obscure ; sori linear- 
oblong, short, the lower ones sometimes double, usu- 
ally abundant, often confluent at maturity and con- 
cealing the narrow membranous indusia. 
On dry and moist rocks, Connecticut and New York to 
Georgia, west to Ohio and Arkansas. Ascends to 4500 ft. 
in North Carolina. June-Aug. 
1o. Asplenium fontanum (L,.) Bernh. 
Rock Spleenwort. (Fig. 55.) 
Polypodium fontanum I,. Sp. Pl. 1089. 1753. 
Asplenium fontanum PBernh. Schrad. Journ. Bot. 1: 
314. 1799. 
Rootstock short, ascending, clothed with narrow 
dark scales at the apex. Stipes tufted, 1/-3/ long, 
somewhat blackish at the base especially on the 
inner side, usually glabrous; leaves lanceolate, 
broadest above the middle, thin, 2-3-pinnate, 3/—6’ 
long, 6’’-1'%%’ wide, acuminate at the apex, nar- 
rowed to the base; pinnae 10-15 pairs, the seg- 
ments deeply dentate with spinulose teeth ; sori 
only 1 to 4 on each segment, covered with a mem- 
branous subentire indusium, rarely confluent. 
On rocks, Lycoming Co., Pa., and Springfield, Ohio. 
The rarest North American fern ; common in Europe. 
Summer. 
