20 



POLYPODIACEAE 



^:--%' -;s■ 





2. Athyrium americanum (Butters) Maxon. 

 Alpine Lady-fern. Fig. 38. 



Athyrium alpestre americanum Butters, Rhodora 19: 204. 1917. 

 Athyrium americanum Maxon, Am. Fern Journ. 8: 120. 1918. 



Rhizomes erect or decumbent, branched, forming 

 massive rounded tufts; scales copious, light to dark 

 brown. Fronds close, 20-90 cm. long ; stipes short, 

 sparsely paleaceous, stramineous from a dark base ; 

 blades linear to oblong-lanceolate, acuminate, 18-65 cm. 

 long, 4-25 cm. broad, usually 2-pinnate-pinnatifid; pin- 

 nae oblique, elongate-deltoid, acuminate, the lower ones 

 distant, usually shorter; pinnules delicately herbaceous, 

 stalked, distant, oblique, narrowly deltoid to oblong- 

 ovate or lance-oblong, incised, or the larger ones pin- 

 nate, the segments incised or biserrate ; sori very 

 numerous, roundish, non-indusiate. 



Moist rocky ravines, meadows, or alluvial thickets, Arctic- 

 ^ .^, Alpine Zone; Alaska to Colorado, Nevada, and the southern 

 i^%j. Sierra Nevada, California (Mineral King) ; also in Gaspe County, 



S^VvS 



Quebec. Type locality: Rogers Pass, British Columbia. 



9. PITYROGRAMMA Link, Handb. Gewachs. 3: 10. 1833. 

 [Cergpteris Link, Fil. Sp. 141. 1841.] 



Small to medium-sized ferns of dryish banks and rock-ledges, the short-creeping tf> 



oblique rhizonies covered with dark rigid linear-lanceolate scales. Fronds erect to drooping, 



clustered, uniform, not articulate to the rhizome, the stipes dark, glossy, firm ; blades 



1-3-pinnate, linear to deltoid-pentagonal, covered with a white to deep yellow powder 



beneath, sometimes glandular above, usually devoid of scales. Sori following the course 



of the veins, usually confluent, non-indusiate. [Greek, in allusion to the furfuraceous sori.] 



About 15 species, mainly of tropical regions, only the following occurring in the United States. Type 

 species, Acrostichum chrysophylhtni Swartz. 



L Pityrogramma triangularis (Kaulf.) Maxon. 



Gold-fern. 



Fig. 39. 



Gymnogramma trianciularc Kaulf. Enum. Fil. 73. 1824. 

 Gymnopteris triangularis Underw. Nat. Ferns ed. 6, 84. 1900. 

 Ceroptcris triangularis Underw. Bull. Torrey Club 29: 630. 1902. 

 Pit\rogramma triangularis Maxon, Contr. U. S. Nat. Herb. 17: 173. 

 "1913. 



Rhizome stoutish, short-creeping or ascending; scales /j 

 linear to lance-attenuate, rigid, brownish, often blackish- 

 carinate. Fronds numerous, clustered, erect, 15-40 cm. 

 long; stipes stout, dark brown, polished, about twice as 

 long as the blades, naked above the base ; blades deltoid- 

 pentagonal, 6-18 cm. long, 5-16 cm. broad, pinnate, or 

 2-pinnate as to the large spreading basal pinnae, these 

 deltoid, strongly inequilateral, with the lower basal seg- 

 ments extended and usually pinnatifid or pinnately divided ; 

 other pinnae mostly oblong, pinnately lobed or incised ; 

 segments rounded-obtuse, mostly decurrent, coriaceous, 

 essentially glabrous above, yellowish-ceraceous beneath, or 

 the powder rarely white or lacking ; sporangia following 

 the short spreading branched veinlets throughout, con- 

 fluent with age. 



Rocky shaded slopes. Upper Sonoran and Transition Zones; British Columbia (Vancouver 

 Nevada (Clark County) and southern California, mainly at low altitudes; also in northern Lower 

 Type locality: San Francisco Bay region, California. 



Island) to 

 California. 



