210 FLORA OF MOUNT DESERT. 



POLYTRICHUM, L. 



P. Ohioense, Ken. & Card. P. formosum, Lesq. & J., Mosses 

 N. A., 264 in part. 



Stem erect, simple or bipartite, 3-6 cm. long, a little tomen- 

 tose below; leaves spreading when moist, erect-flexuous when 

 dry, from a sheathing base, linear-acuminate, cuspidate, serrate ; 

 lamellse about 50, each in section of a row of 5-7 cells, the mar- 

 ginal one much larger, transversely dilated, about twice broader 

 than high, very slightly convex, often almost plane; perichaetial 

 leaves longer, with a longer hyaline base. Pedicel 4-8 cm. long, 

 reddish below, pale above ; capsule erect, finally horizontal, 

 tetragonal or pentagonal, rarely hexagonal, acute-angled, rather 

 narrowed toward the base, with a very small or indistinct hy- 

 pophysis; length 5-7 mm., diameter 2-2 mm.; lid conic-acu- 

 minate, red at margin. Distinguished from P. formosum by the 

 form of the capsule, more or less narrowed toward the base, and 

 with an indistinct hypophysis ; and further chiefly by the form 

 of the marginal cells of the lamellae. Ken. & Card., Kev. Bryol. 

 (1885), 11. Bot. Gaz., xiii. 199. Macoun, Cat. Canadian Plants, 

 part vi. 153. On ground. Woods, Hadlock Valley (Kedfield). 



P. piliferum, Schreb. 



Dry grounds, and in rock hollows. Sargent Mt. ; Browns 

 Mt. (Walter L. Burrage) ; Flying Mt. (K. & K.) ; - Newport 

 Mt. (Theodore G. White). 



P. juniperinum, Willd. 



Dry, open ground. Dog Mt. ; Browns Mt. ; Asticou Hill 

 (Walter L. Burrage) ; Otter Creek quarries (Theodore G. 

 White). 



P. alpinum, L. P. juniperinum, Willd., var. alpinum (L.), 

 Schimp. 



Barr Hill, and elsewhere (Theodore G. White). 

 P. strictnm, Banks. 



Dry ground. Browns Mt. (Kand) ; Southwest Harbor (A. 

 B. Eaton) ; Salisbury Cove (Walter L. Burrage) ; Long 

 Pond (Theodore G. White). 



