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Herbarium — Part 10

Leaves.--Spreading, slightly incurved when dry, pointed, lance-shaped, keeled, smooth, or with tiny projections; base transparent; margin entire or slightly serrate and recurved above the base ; vein vanishing below the apex.

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

Veil (calyptra).--Split up one side.

Spore-case.--Egg-shaped, oblong, or nearly spherical, thick-walled, chestnut colour, shining, top-shaped when dry and empty.

Pedicel.--1/6 to 2/6 of an inch long.

Lid (operculum).--With a long oblique beak, at base attached to central column (columella) in the spore-case, by which it is held long after it has split away from the rim.

Annulus.--Two rows of persistent cells.

Spores.--Mature in late summer.

Distribution.--Common in North America, Europe, and Asia. Very abundant in Niagara Falls.

Genus WEISIA, Hedw.

The species of this genus are small and slender, growing in tufts or cushions on the ground. The leaves are lance-shaped and twisted when dry, the apex is awl-like and the vein single.

The spore-case is erect, oval-oblong, symmetrical or rarely incurved on an erect exserted pedicel. There is but one row of sixteen teeth, often imperfect or wanting, granular and transversely barred.

The generic name Weisia was given in honour of Frederigo Wilhelm Weiss, a German professor of botany.

About twenty-four species are known in all.

Weisia viridula, Brid.

Habit and habitat.--Common, forming more or less compact cushions on the ground in meadows, broken fields, borders of ditches and grassy roadsides, where it is conspicuous for its bright green colour. Very variable.

Name.--The specific name viridula is the Latin diminutive of viridis, green.

Plants (gametophyte).--Stems about 1/4 of an inch long, simple or branched.

Leaves.--The lower minute; the upper much larger, narrowly lance-shaped and curled when dry; base enlarged, pale, concave; vein (costa) stout and extending beyond the apex into a short sharp point; margin inrolled in the upper part to form a tube, flat toward the base; cells opaque, dot-like, with tiny projecting points.

Habit of flowering.--Male and female flowers on the same plant (monoicous).

Veil (calyptra).--Smooth, split on one side and reaching to the middle of the spore-case.

Spore-case.--Light-brown, oval, oblong, of thick texture, slightly constricted under the mouth, wrinkled lengthwise when dry.

Pedicel (seta).--1/6 to 2/6 of an inch long and twisted to the right.

Lid (operculum).--Beak, long, straight or bent obliquely.

Teeth (peristome).--Orange-red, variable, slender or broad, often ending abruptly (truncate) or split into two parts with 2 to 5 cross bars, sometimes rudimentary.

Annulus.--Narrow, persistent.

Spores.--Mature from March to May.

Distribution.--Universal.

Genus TREMATODON, Michx.

The species of the Genus Trematodon are short plants, sparingly branched and forming pale-green or dusky-brown tufts on the ground. The leaves are lance-shaped, tapering toward the apex; a vein is present, and the cells are large and long-hexagonal. The spore-cases are oblong, slightly arched with a long neck (collum) once or twice as long as the spore-case. They have long-beaked lids with conical bases and are raised on slender pedicels 1/2 to 1 1/2 inches long. A simple or compound annulus is present and a single row of sixteen red-brown narrowly lance-shaped teeth cleft to near the base into two unequal forks.

The generic name, compounded of two Greek words: a perforation, and a tooth, was suggested by the character of the teeth of one species, Trematodon ambiguum, which often have a cleft or perforation running lengthwise of each tooth.

There are sixty-four species in all, two in the United States.

Trematodon ambiguum, Hornsch.

Habit and habitat.--Wet sandy places on hills; in peat-bogs, ditches, etc., of Alpine regions.

Name.--The specific name ambiguum, doubtful, was given to this species at the time it was classified in the genus Dicranum (1792) and expressed the doubt as to its rightful position, which was determined in 1803.

Plants (gametophyte).--Short, 1/2 to 1 inch long.

Leaves.--Open, lance-shaped, channelled; apex long and slender; base concave, oval-oblong; margins entire, inrolled; vein extending beyond the leaf-blade (excurrent).

Leaves at the base of the pedicel.--Large, oblong, with a short tapering point. Perichaetial leaves.

Habit of flowering.--Male and female flowers in different places on the same plant (autoicous); male flowers terminal on a basal branch, bracts small, taper-pointed.

Veil (calyptra).--Translucent, slit on one side (cucullate).

Spore-case.--Oblong, straw-coloured or orange-brown; in length equal to or shorter than the slightly arched neck (collum) which is swollen on one side at the base.

Pedicel (seta).--Long, twisted, 1/2 to 1 1/2 inches long, straw-coloured.

Lid (operculum).--Conical at the base; beak, long and oblique.

Teeth (peristome).--Cleft to near the base or in the middle only; segments sometimes irregularly torn.

Annulus.--Large, rolling back when mature.

Spores.--Mature in July and August.

Trematodon longicollis, Michx.

Trematodon longicollis, the long-necked Trematodon, may be distinguished from Trematodon ambiguum by the neck, which is twice as long as the spore-case, by the shorter plants, and by the slender character of the teeth and the leaves at the base of the pedicel. The specific name longicollis is compounded of two Latin roots, longum, long, and collum, a neck.