1. T. latifòlia, L. (Common Cat-tail.) Stout and tall (4–6° high), the flat sheathing leaves 3–10´´ broad, exceeding the stem; the staminate and dark brown pistillate parts of the spike (each 3–6´ long or more) usually contiguous, the latter at length 1´ in diameter; pistillate flowers without bractlets; stigma rhombic-lanceolate; pollen-grains in fours.—In marshes, throughout N. Am. (Eu.)
2. T. angustifòlia, L. Leaves narrower (3–6´´ broad), taller, somewhat convex on the back; pistillate and staminate inflorescence usually separated by a short interval, the light brown spike becoming 5–6´´ in diameter; pollen-grains simple; pistillate flowers with a linear stigma and a hair-like bractlet slightly dilated at the summit.—N. Eng. to N. J., west to Mich. and Mo.; less frequent, and mainly near the coast. (Eu.)
2. SPARGÀNIUM, Tourn. Bur-reed.
Flowers collected in separate dense and spherical leafy-bracted heads, which are scattered along the summit of the stem; the upper sterile, consisting merely of stamens, with minute scales irregularly interposed; the lower or fertile larger, consisting of numerous sessile 1–2-celled pistils, each surrounded by 3–6 scales much like a calyx. Fruit wedge-shaped or club-shaped, more or less corky toward the summit, the hard endocarp perforated at the apex.— Rootstocks creeping and stoloniferous; roots fibrous. Stems simple or branching, sheathed below by the base of the linear leaves. Flowering through the summer. (Name from σπάργανον, a fillet, from the ribbon-like leaves.)
[*] Fruit sessile, broad and truncate, often 2-seeded; stigmas often 2, elongated; scales rigid, nearly equalling the fruit; erect, with branched inflorescence.
1. S. eurycárpum, Engelm. Stems stout, erect (2–4° high); leaves mostly flat and merely keeled; pistil attenuate into a short style bearing 1 or 2 elongated stigmas; fruit-heads 2–6 or more, 1´ wide; fruit many-angled (3½–4´´ long) when mature, with a broad and depressed or retuse summit abruptly tipped in the centre.—Borders of ponds, lakes, and rivers, N. Eng. to Va., west to the Pacific.
[*][*] Fruit comparatively narrow, and mostly somewhat stipitate, 1-celled, longer than the scales.
2. S. símplex, Huds. Stems slender, erect (½–2° high); leaves more or less triquetrous (2½–4´´ wide); fertile heads (1–4) of the usually simple inflorescence often above the axils, sessile or peduncled, 6–8´´ wide in fruit; stigma linear, equalling the rather slender style or shorter; nutlets pale, fusiform or narrowly oblong (about 2´´ long), more or less contracted in the middle.—N. Eng. to N. J., west to Mich., Minn., and northward. (Eu.)
Var. andrócladum, Engelm. Stouter (1½–3° high), with usually broader leaves (4–9´´) and branching inflorescence, the head or peduncles axillary or nearly so; fruiting heads (1–7) often larger (6–12´´ broad), the nutlets 2–3´´ long. (S. androcladum, Morong.)—In bogs or shallow water, common; N. Eng. to Fla., west to Minn. and Mo.
Var. angustifòlium, Engelm. Very slender; leaves floating, long and narrow (½–2½´´ wide), flat; inflorescence simple; heads (4–6´´ broad) and nutlets smaller.—Mountain lakes and slow streams, N. Y., N. Eng., and northward; sometimes nearly out of water, dwarf and with shorter erect leaves.