428 
Proceedings of the Royal Irish Academy. 
Sub-tribe. Thuyidiece. 
67. Thamnitjm. Schimp. 
Peristome as in Hypnnm, but distiuguished chiefly by tlie habit 
of the primary stems of the plants, which are rhizoma- 
tous at their bases ; with flat dendroid branches. Leaves 
ovate-lanceolate, strongly nerved ; areolation rather dense. 
Capsules aggregated, cernuous, with rostrate lids. 
1. T. alopecurum (Linn.). — Bryol. Europ,, vol. v. Monogr., p. 4, 
tab. 518. Briol. Ital., p. ,64. Eabenhor., Bryothec. Europ., 
N'o. 902. Isothecium alopecurum, Bryol. Brit,, p. 324, tab. 25. 
Hypnum alopecurum, Engl. Bot., tab. 1182. Hook, and 
Taylor. Muscol. Brit., p. 168. 
Hab. By the sides of rivulets, and in moist woods. Erequent. 
67^'. Heteroclidium. Schimp. 
Distinguished chiefly by the prostrate radiculose stems, which are 
sparingly villous ; by the leaves, which are of two forms, the 
cauliue being larger and squarrose, the branch-leaves obtuse, 
slightly papillose, roundish, and sub-erect, denticulate, and 
shortly two- nerved at the base ; areolation oblong-hexagonal or 
subquadrate. Capsule cernuous ; lid conic or slightly rostellate. 
Inner peristome with a single filiform process between each of its 
segments. 
1. H. lieteropteron (Br. et Schimp.). Bryol. Europ., vol. v. 
Monogr., p. 4, tab. 480. llabenhor., Bryothec. Europ., ]^os. 
539 and 643. Hypnum heteropteron, Bryol. Brit., p. 369, 
tab. 26. H. atrovirens, Turner., Muse. Hib., p. 169. H. 
catenulatum, MuscoL Brit., Ed. 2, p. 160, tab. 24. 
Hab. Moist rocks near waterfalls, and on broken ground by the 
margins of rivulets. Waterfall at PowersCourt, and Dargle 
river, Wicklow ; Connemara, Galway, &c. At O'Sullivan's 
Cascade, Killarney, in fruit July, 1866. 
68. Myueella. Schimp. 
Stems decumbent, more or less radiculose, and stoloniferous ; innova- 
tions ascending or erect. Leaves slender, cordate-ovate, obtuse 
or slightly pointed, shortly two-nerved at the base. Capsule 
ovate, cernuous, of thick texture. Peristome double, the external 
of 16 strong subulate-acuminate teeth, connected at base ; inte- 
rior peristome with teeth longer than those of the outer; their 
segments broadly lanceolate, irregularly divided along the keel ; 
areolation consisting of quadrate or rhomboid hyaline cells. In- 
florescence dioicous; male flowers gemmiform. 
