28 MUSCI. (MOSSES.) 
21. agi slo Brid. (Tab. 16.) 
Calyptra cuculliform. Operculum conic, obtusely rostrate. Capsule oval 
eblong or cylindrical, paren: a -pedicellate. Peristome single: teeth 16, 
snbulate; 2 —3-cleft, u y a basilar membrane. Inflorescence moncecious 
or dicecious. — Plants ag rather low stature, growing on the ground or on rocks, 
in general habit, ramification, and structure of leaves having much in common 
with Trichostomum and Barbula. — (Name from dopa, -aros, a band, and ddav, 
@ tooth, in allusion to the membrane uniting the teeth. 
1. D. arenhkceus, Sulliv. & Les sqx. (Muse. Bor.-Amer., No. 93.) 
Stems 2-3" high, gregarious; leaves oblong, Rauelotin: very phen: slightly 
denticulate at the apex ; apiculate by the excurrent costa; ca apsule cylindrical, 
tapering into the pedicel (4”-5! long) ; annulus simple, persistent ; teeth of the 
peristome 2-cleft, straight, white. — Sandstone rocks, Ohio. — r D, flavicans, 
Obius, Sulliv. & Lesqx. (Muse. Bor.-Amer., No. 94.) 
Semis 3. 5" high, fastigiately branched ; leaves erect, Binasied-obloher, very 
obtuse, carinate-concave, narrowly aban on the margins; areolation minute, 
nga ak dot-like above, larger oblong and pellucid below; ae excurr sii — 
oth white hair-point nearly as long as the leaf; yli 
its ios orange-red ; operculum 3 the length of the capsule; teeth of the peri- 
y , more or less cloven along the medial line; annulus he : 
diecious. (Barbula muralis, James; not of Hedw.) — Grows in hoary le- 
green and dense patches, on brick pavements, Charleston, S. Carolina, Rave 
on the walls of the College at Nashville, Tennessee, Lesquereux. (Tab. 16.) 
22. DIDYMODON, Br.&Sch. (Tab. 16.) 
Calyptra cuculliform. Operculum conic, shortly and obtusely rostrate. Cap- 
sule nec annulate, long-pedicellate. Peristome single: teeth 16, 
se ear-lanceolate, entire, or more or less bifid, rather short, fugacious, and with- 
rane. Inflorescence various. — Very nearly allied to the last 
genus; and it is questionable if either is es to rank higher t 
han as a section 
of Trichostomum, 
(Name from didvpos, twin, and ddév, a tooth.) (Tab. 16.) 
1. D. rubéllus, Br. & Stems }/~1/ high, loosely cxespitose ; leaves 
sprea — oblong-lanceolate, recurved on the margins, costate to the apex, the 
upper ones dull-green, the lower reddish; annulus simple ; antheridia naked in 
the ails of the perichztial leaves. — Pennsylvania, on the ground ; rare 
(Tab. 16.) (Eu.) 
2. D. Iiiridus, Hornsch. Rather panna than the last; leaves Iurid- 
‘green, rigid, ovate-lanceolate, with a reddish-br wn costa, ceasing at the apex ; 
peristome minute, — male flower ended on a separate plant. — Falls 
(Eu.) 
of Niagara, Drum 
Tre VI. DISTICHIES. 
23. DISTICHIUM, Br. & Sch. (Tab. 16.) 
- Calyptra cuculliform, a Operculum conic, short. Capsule oval- 
