[329] THE MOSSES OF ALASKA 289 



other extreme is var. brevifolitim. In the specimens from Alaska we 

 find all gradations of form between the two varieties. 



Pogonatum alpinum septentrionale Brid. Bryol. univ., n, p. 131. 



From Kodiak (Trelease, 1676) ; St. Paul Island (J. M. Macoun). 

 Pogonatum alpinum arcticum Brid. Bryol. univ., n, p. 131. 



From Egg Island, Disenchantment Bay (Coville and Kearney, 1006) . 

 Pogonatum alpinum brevifolium Brid. Bryol. univ., n, p. 131. 



From St. Paul Island (Trelease, 1661 in part) ; St. Lawrence Is- 

 land (Trelease, 1664) ; St. Matthew Island (Trelease, 1662) ; Plover 

 Bay, Siberia (Trelease, 1670; Brewer and Coe, 667). 



Pogonatum alpinum simplex Sch. Syn., ed. 2, p. 539. 

 From Port Clarence (Trelease, 1665). New to Alaska. 



P. atrovirens Mitt, has been recorded from Alaska by Kindberg. P. micro- 

 dontium Kindb., from St. Paul Island, seems to us not distinct from P. alpinum 

 var. septentrionale. 



Polytrichum formosum Hedw. Spec, muse., p. 92, pi. 19, figs, i, a. 

 From Alaska, sine loco (W. H. Evans in 1897) ; Juneau (Trelease, 

 1681; Canby, 429); New Metlakatla (Trelease, 1678^, 1679); 

 Wrangell (Trelease, 1679 bis; Canby, 434); Farragut Bay (Brewer 

 and Coe, 610) ; Orca (Coville and Kearney, 1306; Setchell, 1204); 

 Virgin Bay (Trelease, 1689); Sitka (Trelease, 1684, 1687; Coville 

 and Kearney, Sn); Hot Springs (Trelease, 1686); Kodiak (Tre- 

 lease, 1694) ; Douglas Island (Trelease, 1682, 1683). 



Polytrichum gracile Dicks. Menz. in Trans. Linn. Soc., iv, p. 73, 

 pi. 6, fig. 3. 

 From Kodiak (Trelease, 1675). New to Alaska. 



Polytrichum commune Linn. Spec, pi., n, p. 1109. 



From Alaska, sine loco (W. H. Evans in 1897) ; between Cook 

 Inlet and the Tanana River (Capt. E. F. Glenn in 1899) ; Kodiak 

 (Trelease, 1693; ^" J' Cole). 



Polytrichum yukonense sp. nov. 



(PI. XXII, fig. I"-/.) 



Caulis 58 centim. altus, simplex vel parcissime ramosus, inferne 

 longe denudatus, basi tomento albido obtectus. Folia rigida, sicca 

 suberecta, madida erecto-patentia, 4-6 millim. longa, i lata, e basi ap- 

 pressa subvaginante lutescente breviter lineari-acuminata, in cuspidem 

 fuscam integram attenuata, marginibus erectis integris, lamellis circiter 

 30, elatis, margine crenulatis, in sectione transversali e 8 1 2 cellulis 



