62 BRYACE^. [Dichodontiam. 



1. D. pellucidum, Schimp. Leaves pellucid at the oblong 

 base, linear-lanceolate, hyaline-serrate, papillose on both faces, 

 borders flat, opaque ; costa naiTOw, crenulate toward the apex, 

 vanishing below : capsule suberect, broadly oval or subglobose ; 

 pedicel soft, flexuous, pale yellow; lid obliquely long-beaked 

 from an enlarged concave base ; teeth of the peristome densely 

 articulate, dark red below, orange above. — Syn. Muse. 65. 

 Z^icranum lyellucidimi^ Hedw. Sp. Muse, 142 ; Bi-yol. Eur. 

 t. 50 and 51. Angstroeniia pellucida^ Muell. 



Var. Americanum, Lesq. Leaves twisted-crispate when 

 dry, shorter and narrower ; cells of the basilar areolation longer : 

 capsule longer. 



Var. serratum, Schimp. Stems longer; leaves larger 

 and coarsely dentate toward the apex : capsule oblong, nearly 

 erect. 



IIab. Cascade Mountains (Lyall), Fort Yale (Maconn) ; the first variety 

 at Brattleborough, Vermont (Frost), and in deep glens, New Jersey and 

 New York (Austin)', var. serratum, Oregon (E. Hall). 



2. D. Canadense. Stem stout, simple: leaves enlarged 

 and clasping at base, subulate-lanceolate, divaricate above, serru- 

 late on the borders ; costa strong and percurrent ; cells of the 

 areolation elongated at base, somewhat oblong above, the mar- 

 ginal shorter, all pellucid : capsule turbinate, unequal, with a 

 broad orifice ; pedicel long, red ; teeth of the peristome large, 

 red, dicranoid. — Ci/nodonthcm Canadeiise, Mitten, Journ. 

 Linn. Soc. viii. 17. Dicranella Schreheri, var. occide7itale, 

 Austin, Bull. Torr. Club, vi. 344. 



Hab, British America, probably from the Rocky Mountains (Drum- 

 mond, n. 101, in part). 



Comparable to Dicranella squarrosa, from which it differs in the leaves 

 more narrowly subulate and with the borders serrulate. It should per- 

 haps be placed under Dicranella; 



19. TREMATODON, Michx. (PI. 1.) 

 Plants short, loosely cespitose, sparingly branching. Leaves 

 lanceolate-subulate, costate ; cells of the areolation large. 

 Flowers autfficious. Capsule long-pedicellate, oblong, slightly 

 arcuate, with a long narrow collum. Operculum long-subulate. 

 Annulus simple or compound. Teeth of the peristome narrowly 

 lanceolate, cleft to near the base or lacerate, purple. 



