386 Proceedings of the Royal Irish Academy. 
Tribe 6. Oethoteichejj. 
1. 0. CAPULITUM. 
37. Oethotrichum. Hedw. 
Calyptra large, campanulate, plicate, lacerate, or crenate, at the base ; 
glabrous or hairy. Capsule immersed or exserted, pyriform, 
clavate, apophysate, 8 or 16 -ribbed when dry. Peristome sin- 
gle or double, rarely absent. Outer peristome of 16-teeth, 
mostly in pairs, with a medial line ; inner, 8 or 1 6 cilia, alternat- 
ing with the outer teeth. Leaves costate almost to the points, 
usually revolute at their margins ; often twisted and curled when 
dry ; areolation small dot-like in upper portion, larger and more 
pellucid at the base. Inflorescence monoicous or dioicous. 
Diagnosis of Species, 
a. Peristome single. 
Capsule immersed, or slightly exserted. 
Capsule with 1 6 furrows ; teeth of the peris- 
tome 16, free and equidistant. 
Capsule with 16 furrows, alternately long 
and short, exserted on a pedicel ; teeth of 
peristome 16, geminate, ultimately free, 2. 0. anomaltjm. 
Capsule with 8 furrows, chiefly on upper 
portion, exserted on short pedicel ; teeth 
of peristome connected in 8 pairs, erect, 3. 0. saxatile. 
Capsule scarcely longer than perichaetal leaves, 
ovate, smooth when fresh, slightly fur- 
rowed near the apex when dry ; teeth 1 6, 4.0. STTJEMn. 
aa. Peristome double, outer of 8 teeth. 
Capsule slightly exserted, subcylindrical, with 
8 ribs ; calyptra conical, slightly hairy, 5. 0. tenellum. 
Capsule slightly exserted, obovate; cilia 8 
or 16; calyptra campanulate ; vaginula 
hairy, 
Capsule sessile, elliptic ; calyptra campanu- 
late, smooth ; cilia 8, . 
Capsule immersed ; calyptra naked, campanu- 
late; cilia 8 or 16 ; leaves bluntish, . 8. 0. pallen^s. 
Capsule pear-shaped, striated ; calyptra 
naked; teeth of peristome in 8 pairs ; cilia 
1 6 ; leaves flaccid, spreading, . . 9. 0. eivulaee. 
6. 0. steamin-etjm. 
7. O. PTJMILTJM. 
