This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Perennial tufted slender herbs, with short rootstocks, simple or branched 2-edged or 2-winged stems, linear grass-like leaves, and rather small mostly blue terminal flowers umbellate from a pair of erect green bracts. Perianth-tube short or none, the 6 spreading segments oblong or obovate, equal, mostly aristulate. Filaments united to above the middle in our species. Ovary 3-celled, each cavity several-ovuled. Style-branches filiform, undivided, alternate with the anthers. Capsule globose, oval or obovoid, loculicidally 3-valved. Seeds subglobose or ovoid, smooth or pitted, dry.
About 150 species, all American. Besides the following, many others occur in the southern and western states, some in Mexico and a few in the West Indies. Type species: Sisyrinchium Bermudiana L., which has larger flowers and fruit than any of ours, and is found only in Bermuda.
Filaments free above; anthers about 2" long: spathes 2, sessile.
Filaments united to the top; anthers about 1" long.
Spathes 2 together, sessile; stem simple.
Spathes solitary at the end of the stem or branches.
Stems simple (occasionally branched in S. angustifolium).
Capsules 2 - 3" high; pedicels ascending.
Capsules less than 2" high; leaves very narrow.
Margins of the outer bract united-clasping below.
Margins of the outer bract separate to the base.
Stems branched above, the several spathes long-stalked.
Basal leaf-sheaths persistent as tufts of fibers.
Basal leaf-sheaths not persistent.
Stems broadly winged; pedicels spreading.
Stems narrowly winged.
Peduncles strictly erect.
Peduncles diverging or ascending.
Very slender and stiffly erect, dull gvcen, about 1° high. Stems 1/2" wide or less, compressed-subterete and bluntly two-edged, not at all winged, closely striate, minutely granulose-roughened; leaves similar to the stems, usually shorter, thick-edged, obtusely slender-pointed, the conduplicate broadened base smooth and membranous; spathes usually two in a close pair at the top of the stem, each usually 4-bracted, the bracts lanceolate-attenuate, the inner ones about 1' long; primary bract much prolonged; interior scales ample, sometimes slightly exserted; flowers few, pedicels not longer than the inner bracts; young capsule longer than thick. Fruit and color of flower unknown.
Sandy shores of Belle Isle in the Detroit River, Mich. Much resembles S. Pringlei Rob. & Greenm. from Jalisco, Mexico. Early June.