328 FRYE 



12. Polytrichiim pilifenim Schreb., in Spic. fl. Lips. p. 74, (1771). 

 Polytrichum pilosum Neck., in Meth, M. p. 123, (1771). 

 Polytrichum laevipilwn Hampe, in Linn. 1859. p, 459. 

 Polytrichum pilijerum var. hoppei Rab.'^ in Deutsch. Kryptfl. II, P. 

 Ill, p. 238 (1848). 



Name derived from pilus = hair, and ferre = to bear; referring 

 to the long hyaline arista at the tip of the leaf. 



Plants in loose tufts, glaucous green, 2.5-4 cm. high. Stems 

 erect, simple, rarely forked, naked at base. 



Leaves when dry closely appressed and straight forming a narrow 

 ovoid or clavate head, leaf-base longer and narrower than in P. 

 sexangulare, limb narrowly lanceolate, apex below arista minutely 

 scabrous; leaves of antheridial plants shorter and more shortly 

 aristate. Margins broadly inflexed and almost meeting, entire, 

 of very narrow transversely elliptical cells. Lamellae about 30, 4-7 

 cells high; marginal cell larger than the others, ovate or flask-shaped, 

 not papillose. Vein reddish, at apex suddenly becoming hyaline, 

 excurrent as a long denticulate hyaline arista, smooth at back. 

 Perichaetial leaves longer than the foliage leaves; inner ones thin, 

 whitish, without lamellae, longly aristate. 



Calyptra covering the capsule. 



Capsule erect, small, inclined when dry, shortly oblong, with 4 

 sharp angles and occasionally a fainter intermediate one ; hypophy- 

 sis indistinct, short, constricWd above where it joins the capsule. 

 Lid red or orange, shortly and stoutly beaked. Pedicel 2.5-4 cm. 

 long. — On rocks and soil. — Lake Lindeman, Yukon, British America; 

 Vancouver Island and eastward in British Columbia to the Rocky 

 Mountains; Washington; California; Uinta Mountains, Utah; 

 eastern British America; Greenland; Europe; Asia; South America. 



*^ The distinctions between P. pilifenim and its variety hoppei do not seem to war- 

 rant a variety. For example, in Fig. 30, Nos. i, 2, 5, and 12, from the same plant, are 

 variety hoppei in leaf tips, plant form and capsule; but the nodding capsule does not 

 agree. Nos. 4, 6, and 13, from another package are variety hoppei in form of capsule 

 and possibly in leaf arrangement, but hardly in leaf tips; also disagreeing in that many 

 of the capsules in this material not shown are nodding. No. 7 is not variety hoppei 

 in form, but the leaves in this plant were very long awned. The length of the awn does 

 not vary constantly with the form of the capsule nor with the length of the leaf. It is 

 believed therefore that variety hoppei is P. piliferum prematurely dried or growing 

 under very adverse conditions, and varying sometimes in capsule, som Jtimes in leaf. 



