Plant Guide > Mosses and Lichens > Mosses > Genus Ceratodon > Purple Horn Tooth Moss

Purple Horn Tooth Moss

The Purple Horn-tooth Moss, Ceratodon purpureum, Brid.

Habit and habitat.-Look for the Purple Horn-tooth Moss on rocky ledges in open sunny places of the woods, in pastures and along roadsides, and in vacant city lots. Bright-green cushions of this moss may be found in depressions of the rocks during February and March. At this time the pedicels are often numerous and well-grown and their wine-red colour makes the moss conspicuous even while the spore-cases themselves thus early in the season are but little larger in diameter than the pedicels and are concealed by their veils. With the approach of warmer weather they mature rapidly still carrying their transparent veils. These are discarded before a great while and then the spore-cases and their conical short-beaked lids are glossy and wine-red. Later the lids fall, exposing a fringe of horn-like teeth about the rim. The sporecases finally become deeply furrowed, inclined, and contracted below the mouth and in this condition may be found during most of the year.

Name.-The specific name purpureum is the Latin for "purple," It refers to the colour of the spore-cases and pedicels.

Plant (gametophyte). -Slender, erect, branching from the base of the pedicels ; stems 1/2 to 3 inches long.

Leaves.-Lanceshaped, keeled; vein extending to or beyond the apex ; margin somewhat irregularly toothed reflexed, opaque ; surface with slight protuberances; cells distinct.

Habit of flowering.-Male and female flowers on separate plants (dioicous).

Veil (calyptra).-Smooth, transparent, split on one side.

Spore-case.-Long, egg-shaped with a short neck, dark-red, erect, somewhat arched ; four- or five-angled and deeply furrowed when dry.

Pedicel.-Slender, wine-red, erect.

Lid (operculum).-Conical, short-beaked.

Teeth (peristome).-Purple, each split into two equal, strongly cross-barred segments, with tiny projections toward the apex.

Annulus.-Large, rolling back as the lid falls. Spores.-Mature in early spring, when they are ousted by the shrinking of the wall tissue.

Distribution.-Almost universal.

Variety Xanthopous.-Greek; yellow, and; a foot; has a pale-yellow pedicel.

Variety Aristatus.-Latin "awned "; has the spore-case and pedicel pale and the mid-vein of the leaf extending beyond the apex of the leaf blade.

Variety Minor.-Latin "smaller"; is said to have narrower teeth jointed only from the middle downward.