musci. (mosses.) 667 



Tribe XXXV. HYPNE^. 



80. HYPR1UM, Dill. (Tab. 19.) 



Calyptra dimidiate, small, fugacious. Operculum between hemispherieal- 

 apieulate and conic-rostrate. Capsule ovate or cylindrical, more or less une- 

 qual, usually arcuatc-cernuous. Peristome double; the exterior 16 linear-lan- 

 ceolate articulate teeth, marked on the back by a medial line, and cristate on 

 the inner face by projecting cross-bars ; the interior 16 carinate processes or 

 cilia, arising from a plicate membrane, with 1-3 ciliolae between each pair. 

 Inflorescence monoecious, dioecious, or polygamous. — A genus, as generally 

 received, embracing a very large number of species, which, presenting in habit 

 and sn-ucture great diversity, may for the most part be combined into natural 

 groups, many of them seemingly of generic value. (Yttvov, an ancient Greek 

 name for some sort of Moss.) 



§ 1. THUIDIUM, Bryol. Europ. — Stems profusely villous, prostrate or ascend- 

 ing, 1 - 3-pinnate ; branchlets mostly short, slender, crowded : stem-leaves broadly 

 ovate, long-acuminate; those of the branchlets much smaller, ovate, and ovate-lance- 

 olate ; all papillose ; areolation dot-like, granulated, opaque ; costa subcontinuous, 

 translucent : capsule oblong-oval, or cylindrical, more or less cernuous : opercidum 

 hemispherical-apiculate or conic-rostrate. 



1. M. taiS&an'iiscsiiUBll, Hedw. Dioecious; stems prostrate ; ramification 

 closely 3-pinnate ; stem-leaves with rcficxed and crenulate-denticulate margins ; 

 branch-leaves ovate-lanceolate ; perichsetial leaves fringed on the margin ; oper- 

 culum conic-rostrate. — On the ground and old logs. — A large and very com- 

 mon species. (Eu.) 



2. H. (lelacfitaalaaiaa, L. Dioecious ; very much like the preceding, 

 but its ramification only 2-pinnate ; operculum conic, acuminate, not rostrate ; 

 perichsetial leaves not fringed — On the ground, in dry places. — Mountains of 

 Pennsylvania : rare. (Eu ) 



3. M. llliaaaafaiStaiaa, Hedw. Monoecious ; smaller than the preceding, 

 with a simply pinnate ramification; capsule horizontal, oval, nearly regular ; 

 operculum large, convex-conic, with a long slender beak. — On decayed logs, in 

 woods; not rare. (Eu.) 



4. EI. pygfameaaaaa, Bryol. Europ. (Muse. Bor.-Amer. No. 275.) Much 

 smaller than the last ; ramification 2-pinnate ; leaves more suddenly acuminated ; 

 perichtetial leaves elongated, with a more lax reticulation. — Shaded ravines, on 

 limestone rocks, Central Ohio ; growing with II. minutissimum. — Among the 

 smallest of the Hypna. 



5. II. scstaam, Beauv. Monoecious ; intermediate in size between No. 

 2 and 3 ; ramification pinnate ; easily recognized by its cylindrical, nearly regu- 

 lar, and erect capsule, with a conical, shortly rostrate operculum. — Hilly dis- 

 tricts, on the base of trees, particularly the Beech. 



6. H. gB'^icale, Br. & Sch. Monoecious ; size and ramification as in the 

 last ; capsule oblong, incurved-cernuous : operculum convex-conic, apiculate. — ■ 



