24 
FERNS OF THE WEST. 
* Fronds pinnate., or several times parted. 
71. Pe alpestris, Mettenius. alpine V .') 
Fronds oblong-lanceolate, acuminate, smooth, pinnate; pinnae twice- 
parted, deltoid-lanceolate; final divisions from ovate-oblong to lanceo- 
late, twice cut or toothed. Rootstock short' and thick. i to 3 feet high, 
i^Potypodiiun , Hoppe ; Aspidium , Swartz. ) 
Around rocks in dense patches; Lassen’s Pealc (California) to British Columbia. 
Europe. Resembles Asplenium Filix-foemina. 
72. p. polypodioMes, Fee. (The P. like Fotypodium.) 
Fronds twice-parted, deltoid-ovate, hairy on the veins; lowest pair 
of primary divisions turned downwards; final divisions oblong, entire, 
obtuse. Rachis winged. Rootstock very slender. 8 to 18 inches high. 
^Foly podium Fhegopteris, L. ) 
Damp woods. Said to occur at San Jose (California). In the Rocky Mountains 
and eastward. Alaska. Europe and Asia. 
* * Fronds divided into three stalked, once- or twice-pinnate divisions. 
73. P. Bryoptcrls, Fee. {PY\\q.Y. like Dry Opteris. Oak-Fern.) 
Fronds smooth; divisions triangular; final divisions oblong, toothed 
or entire, obtuse. {Folypodium , L.) 
Damp woods. Oregon and eastward. 
XIII. ASPIDIUM, Swartz. Shield-Fern. Wood-Fern. 
Indusium attached to the center of the fruit-dot by a short stalk, or 
attached on one side at the margin. Veins free in our species. (From 
the Greek, meaning a little shield, in allusion to the indusium.) 
A genus of over 3CX) species, chiefly tropical ; 23 species in the United States. 
* Indusium kidney-shaped or round, fixed by one side. 
-i— Veins forking but once. Tlirn or papery ferns. Fronds pinnate ; fruit- 
dots close to the margin. Rootstock thick, creeping. 
74. A. Nevadense, Eaton. (From the Sierra Nevadas.) 
Stalks short. Fronds narrowly lanceolate, pinnate; lower pinnae 
gradually reduced in size, linear-lanceolate, broad at base, almost sessile, 
deeply cut ; final divisions oblong, nearly entire, obtuse, somewhat hairy 
on the veins, resinous dotted ; indusium minute, hairy, glandular. 2 to 
3 feet high. 
Shady and moist places in the Sierras of California. Resembles A. Noveboracense, 
except in the rootstock. 
75. A. patens, Swartz. (The open A.) 
Fronds ovate-oblong, softly pubescent; lower pinnae not reduced, 
linear, acuminate, pinnately parted; final divisions oblong, somewhat 
acute ; indusium very pubescent. i to 3 feet high. (yNephrodium , 
Desvaux.) 
In canyons; southern California, Texas to Florida and southward. Polynesia and 
South Africa. 
Veins forking freely ; frond not papery ; rachis usually scaly, as well 
as the stalk. Rootstock short and thick. 
