Triangular Wood Reveller MossThe Triangular Wood-reveller, Hypnum (Hylocomnium) triquetrum, Linn.
Habit and habitat.-In large yellow or light-green mats 4 to 8 inches deep, on decayed wood in plains and mountains.
Name.-The specific name triquetrum was given to the moss by Linnaeus to describe its habit of pointing its branches in three directions, the Latin triquetrum meaning "having three angles."
Plants (gametophyte).-Stems stout and rigid, erect, simple or slightly divided, branched unequally and irregularly or with feather branches not all in the same plane.
Leaves.-Very large, horizontally spreading both when wet or dry, stiff and membranous, glossy, triangular; apex acute; vein double to the middle; margin closely toothed; base auriculate; cells of the basal angles wide, transparent, oblong six-sided. Branch-leaves narrower, and gradually smaller upward.
Habit of flowering.-Male and female flowers on separate plants (dioicous).
Veil (calyptra).-Split up one side.
Spore-case.-Oblong, horizontal or inclined by a curve of its pedicel under the base, narrowed at the mouth when dry.
Pedicel (seta).-Curved below the spore-case, 1 to 1 1/2 inches high.
Lid (operculum).-Convex with a tiny point in the centre. Annulus.-Simple.
Teeth (peristome).-As in the genus Hypnum. Spores.-Mature in, autumn and winter.
Distribution.-Common in Europe; widely spread in America; common in the Adirondacks.