FERN FAMILY 9 



4. POLYSTICHUM Roth, Rom. Arch. Bot. 2^ : 106. 1799. 



Coarse, large to rather small ferns of ledges and rocky woods, the stout woody rhizomes 



mostly erect to decumbent, copiously paleaceous. Fronds several, rigidly ascending or 



recurved, borne usually in a crown, the blades similar or subdimorphous, simple to 3-pinnate- 



pinnatifid, more or less paleaceous, the segments of harsh texture, mainly auriculate, usually 



with serrate margins, the teeth pungent to spinulose or aristate ; veins free. Sori round, 



dorsal to subterminal ; indusia superior, orbicular, centrally peltate, persistent to caducous, 



or sometimes wanting. [Name Gre.ek, meaning many rows, alluding to the numerous regular 



rows of sori in P. loncliitis.} 



A genus of about 100 species, mainly of boreal and temperate regions, agreeing closely in habit. Type 

 species', Polypodium lonchitis L. 



Blades simply pinnate, the pinnae variously serrate to evenly incised, never pinnately lobed to pinnatifid. 



Stipes very short; pinnae mostly oblong-lanceolate (the lower ones deltoid), serrate-dentate, the teeth 

 conspicuously spreading-spinulose. 1. P. lonchitis. 



Stipes much longer; pinnae linear-attenuate, biserrate to incised, the teeth incurved, rigidly long-aculeate. 



2. P. niuiiituiii. 



Blades more compound, the pinnae at least pinnately lobed or divided at the base. 



Pinnae pinnately lobed to pinnatifid at the base. 



Segments very numerous, small, the lobes merely crenulate-dentate. 3. P. lemmoui. 



Segments few, large, pungent to spinulose-aristate. 



Pinnae inequilateral, deltoid-ovate to deltoid-oblong, the lobes and teeth pungent but not aristate. 



4. P. scopulinum. 



Pinnae larger, linear from a broader base, the lobes more numerous, distinctly aristate. 



5. P. calif ornicum- 



Pinnae nearly or quite pinnate. 



Blades proliferous below the tip, slightly scaly beneath; teeth long-awned; indusia erose-dentate. 



6. P. andersoni. 



Blades not proliferous, copiously scalv beneath; teeth short-awned; indusia long-ciliate. 



/. P. dudteyi. 



1. Polystichum lonchitis (L.) Roth. 



Hollv-fern. 



Fig. 17. 



Polypodium lonchitis L. Sp. PI. 1088. 1753. 



Polystichum lonchitis Roth, Rom. Arch. Bot. 2': 106. 1799. 



Aspidium lonchitis Swartz, Journ. Bot. Schrad. 1800=: 30. 1801. 



Rhizome large, woodj', erect or decumbent. Fronds sev- 

 eral, rigidly ascending in a close crown, 15-60 cm. long; 

 stipes 1-6 cm. long, thick, stramineous, densely paleaceous, 

 the scales rusty brown, mostly large, ovate, denticulate; 

 blades linear to narrowly linear-oblanceolate, acuminate, 

 12-55 cm. long, 2-7 cm. broad, tapering at the base, simply 

 pinnate, the rachis very stout, deciduously paleaceous ; 

 pinnae numerous, close, the basal ones deltoid (sometimes 

 minute), equilateral, the middle and upper ones oblong- 

 lanceolate, falcate, acute, auriculate above, cuneate below, 

 unevenly serrate-dentate, the teeth conspicuously spread- 

 ing-spinulose ; sori large, contiguous, usually in 2 rows, 

 nearly medial; indusia large, entire; leaf tissue evergreen, 

 subcoriaceous, fibrillose beneath. 



Rocky shaded slopes, in the Boreal region; Alaska to Nova Scotia, southern Ontario, Michigan, and 

 Montana, and in the mountains to Utah, Colorado, and northern California (Castle Lake, Siskiyou County); 

 also in Greenland: Eurasia. Type locality, European. 



