WILLIAMS: THE GENUS DESMATODON 215 
ated; seta erect, mostly 7-10 mm., rarely 13 mm. long; capsule 
erect, nearly straight and cylindric, about 2 mm. long without lid, 
with a conical more or less short-beaked lid 0.50-0.75 mm. long, 
the cells from a little above the base mostly oblong in slightly 
oblique rows; annulus large, persistent, of two or three rows of. 
cells; peristome papillose, reddish or golden brown, the erect or 
nearly erect teeth from a basal membrane projecting a little above 
the annulus and irregularly divided into two or three forks, or the 
forks sometimes more or less united; spores smooth, about 8 w in 
diameter; calyptra cucullate, long-beaked, extending one third 
way down the capsule. [Fic. 6.] 
TYPE LOCALITY: Easton, Pennsylvania. 
DisTRIBUTION: Gaspé coast, Quebec, and Point Pelee Island, 
Lake Erie, Ontario, to Pennsylvania, Ohio and Illinois. 
ExsiccaTAaE: Aust. Musci App. 123. 
ILLUSTRATION: Sull. Ic. Musc. Suppl. pl. 23. 
. DESMATODON systyLius B.S.G. Bryol. Eur. (18-20): Desma- 
todon, Suppl. 1. 1. 1843 
~I 
Paroicous, the antheridia about 0.25 mm. long, in one or two 
pairs, without paraphyses, in the axils of the outer perichaetial 
leaves: plants cespitose, somewhat branching, usually 2-3 mm. 
high, often more or less bud-like; the upper stem leaves with blade 
about 1.5 mm. long and I mm. wide, broadly ovate, acute, the 
margins mostly flat and entire or slightly crenulate at apex and 
the costa excurrent into a nearly smooth, flexuous, hair-point of 
variable length; the costa in cross-section showing two, guide-cells — 
with two often larger cells on the ventral side and on the dorsal 
side a large stereid band with differentiated outer cells; cells of 
upper part of leaf from nearly square to rhomboidal or hexagonal, 
somewhat mamillose, the median 15-20 in diameter, in lower 
Part mostly rather larger and elongate-hexagonal or short-rect- 
angular; perichaetial leaves scarcely differentiated; seta erect, 
about 8 mm. long; capsule erect, oblong-cylindric, up to 2 mm. long 
without lid, the columella exserted, persistent, the stomata in 
about two rows near base; annulus persistent, of one or two rows of 
cells; peristome teeth reddish brown, papillose, mostly divided to 
near the base into two forks, erect from a rather low basal mem- 
brane; lid remaining more or less attached to the columella after 
separating from the annulus, obliquely short-beaked, the cells, 
€xcept the three of four basal rows, elongate, in slightly oblique 
Tows; calyptra cucullate, descending well down the capsule; spores 
Tough, up to 254 in diameter. [Fic. 7.] 
