Part 2, 1913] DICRANACEAE 101 
vertically striate, the inner articulations distinct, about 20 u apart: lid convex with an oblique 
beak; annulus none: spores rough, 20-24 » in diameter. 
TYPE Locality: Hector, in the Rocky Mountains of British Columbia. 
DISTRIBUTION: Known only from the type locality. 
Exsice.: Macoun, Can. Musci 518. 
7. Oncophorus tenellus (B.S. G.) R.'S. Williams. 
Dicranum gracilescens tenellum B. S. G. Bryol. Eur. (37-40:) Dicranum 13. 1847. 
Cynodontium alpestye Milde, Bryol. Siles. 51, in part. 1869. . 
Cynodontium tenellum Limpr. Krypt.-Fi. Schles. 1: 425. 1877. 
Cynodontium torquescens Limpr. in Rab. Krypt.-Fl. 41: 288. 1886. 
Dicranum torquescens Bruch; Limpr. in Rab. Krypt.-Fl. 41: 288, as synonym. 1886. 
Cynodontium subalpesire Kindb.; Macoun, Cat. Can. Pl. 6: 257. 1892. 
Autoicous: male flower at the base of the perichaetium, of mostly 2 obtuse, ovate to oblorig- 
‘linear leaves, costate below: plants in usually rather low, compact, yellowish-green cushions 
with branching stems radiculose below and rarely more than 1 or 2 cm. high: stem-leaves up 
to 3 mm. long and about 0.2 mm. wide, crispate when dry, linear-lanceolate, obtusely or 
acutely pointed and from nearly entire and smooth throughout to rough on the margins and 
surfaces in the upper half, the borders more or less recurved and of a double thickness of cells 
along the middle; costa mostly vanishing in the apex, smooth on the back throughout or 
slightly rough above; upper leaf-cells rather variable, about 8 » wide, mostly scarcely elongate, 
or sometimes twice as long as wide, with slightly thickened walls, usually smooth or nearly so 
ou both sides except near the margins, those toward the base rectangular, those at the angles 
often wider, nearly square, sometimes slightly inflated; perichaetial leaves similar to the upper 
stem-leaves, loosely clasping about one half up: seta brownish, straight, up to 1 em. long: 
capsule oblong, mostly nearly erect and regular, not strumose, furrowed when dry; lid entire on 
the border, with an oblique beak one half as long as the capsule; peristome-teeth reddish-brown, 
mostly divided two thirds or more down into 2 forks, papillose above, the outer plates vertically 
striate, the inner articulations prominent, mostly about 20 apart; annulus wanting: spores 
rough, up to 20 uw in diameter. 
TYPE LocaLity: Germany. . 
DistRiBuTION: Labrador and Alaska to the mountains of New England and Montana; also 
in Europe and Asia. ee } 
Exsicc.:|Aust. Musci App. 467//Sull. & Lesq. Musci Bor. Am. 44; ed. 2. Dea Ole, Musci Acroc. 
Bor. Am. 304. an 
8. Oncophorus virens (Sw.) Brid. Bryol. Univ. 1: 399. 1826. 
Bryum virens Sw. Nova Acta Soc. Sci. Upsal. 4: 241. 1784. 
Dicranum virens Hedw. Descr. 3:77. 1792. 
Cynodontium virens Schimp. Coroll. Bryol. Eur. 12. 1855. 
Autoicous: one or more male flowers sessile at short intervals below the perichaetium, of 
mostly 4 or 5 usually ovate, actite, entire, costate leaves enclosing 4 or 5 antheridia with few 
paraphyses: plants in usually rather extensive, not very compact, green cushions with branching 
stems somewhat tomentose below and 4-5 em. high or more: stem-leaves more or less crispate 
when dry, up to 4 mm. long, from an ovate base usually somewhat abruptly narrowed to a 
lanceolate, nearly entire or irregularly serrate, acute point, the borders mostly recurved from 
a little below the point to near the base and of a double thickness of cells; costa mostly shortly 
excurrent, smooth on the back or nearly so, about 100 « wide at the base and one sixth of the 
leaf-width, in cross-section near the middle showing about 6 guide-cells, often 1 or 2 accessory 
cells nearly as large, and rather poorly differentiated stereid-bands above and below with some- 
what distinct outer cells; leaf-cells distinct and nearly smooth throughout, the median often 
scarcely elongate, the lower ones paler, brown, laxly rectangular, 8-10 u wide by 40» long, 
with thin walls, those at the angles usually forming rather distinct, darker brown, somewhat 
inflated alar groups; inner perichaetial leaves up to 5 mm. long, loosely clasping scarcely one 
half up and rather abruptly narrowed to a smooth point: seta yellow, erect, up to 3 cm. long: 
capsule oblong, curved, strumose, smooth when dry or somewhat furrowed; annulus wanting; 
lid not quite entire at the base, with an oblique beak one third as long as the capsule; peristome- 
teeth reddish-brown throughout, divided scarcely one half down, vertically striate to near 
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