THE POLYTRICHACEZ OF WESTERN NORTH AMERICA 303 
4b. P. alpinum var. brevifolium?® Brid., in Sch. Syn. I. ed. p. 
441, (1860). 
Polytrichum alpinum var. brevifolium Muell., in Syn. I, p. 210, (1849). 
1. Leaves about 7-8 mm. long. 
2. Leaf-sheath to blade about as 1:3-3%. 
3. Plant about 4 cm. tall or shorter. 
4. Capsule 3-4 mm. long. 
5. Width of capsule to length as 1:13-23. 
6. Stems with few and short branches. 
7. Pedicel 24—24.cm. long. 
a. Capsule with distinct neck. 
On rocks.—Islands of Bering Sea; Mt. Dana, California; Hudson 
Strait; Greenland; mountains of Europe; Siberia. 
4c. P. alpinum var. septentrionale?’ (Sw.) Brid., in Sch. Syn., 
t ed., p. 441 (1860): 
P. alpinum var. microdontium*®! Kindb., in Mac. Cat. Vol. 6, p. 
152, (892). 
1. Leaves about 7-8 mm. long. 
2. Leaf-sheath to blade about as 1:3-34. 
3. Plants about 5 cm. tall or shorter. 
4. Capsule 3-4 mm. long. 
5. Width of capsule to length as 1:14-24. 
6. Stems simple. 
7. Pedicel 14-2 cm. long. 
a. Capsule without distinct neck. 
On soil and rocks.—Islands of Bering Sea; Kodiak Island, 
Alaska; mouth of Skeena River and Rocky Mountains, British 
Columbia; Europe. 
4d. P. alpinum var. arcticum”? (Sw.) Brid., in Sch. Syn. 1 ed- 
Pp. 441 (1860). 
Polytrichum sylvaticum Menz., in Trans. Linn. Soc. 4. p. 83, n. 
19 (1798). 
Polyirichum alpinum var. arcticum Wahl., in Fl. Lapp., p. 346 
(1812). | 
19 Breve = short, folium = leaf; because its leaves are shorter than those of nearly 
all other varieties. 
20 Septentrionale = pertaining to the north; referring to the northern habitat of 
this variety. 
21 Examination of Alaskan collections leads to the conclusion that Cardot and Thériot 
are right in concluding that var. microdontium does not separate from var. sepientrionale. 
22 So named on account of its arctic habitat. 
Proc. Wash. Acad. Sci., August, 1910. 
