IXIACEAE 295 
Inflorescence scant, with 1 or sometimes 2 nodes, each bearing 1 or 2 peduncles. 
Plants mostly over 30 em. tall, when lower very delicate and slender. 
Leaves much shorter than the straight wing-flattened 
scapes: capsules 2-4 mm. long. 31. S. Atlanticum. 
Leaves equalling the flexuous subterete scapes : capsules 
4-6 mm. high. 32. S. flexile. 
Plants 15-30 em. tall, somewhat stiff or rigid. 
Perianth becoming 15 mm. long: staminal column 5 
mm. high: bracts of the spathe finely puncticulate- 
dotted. 33. S. violaceum. 
Perianth about 10 mm. long: staminal column 4 mm. 
high or less: bracts of the spathe not dotted. 84. 
Inflorescence more contracted and compound, mostly with 2-4 
nodes each bearing 2-4 peduncles. 
Seapes 1.5-8 mm. wide: perianth over 10 mm. long, the 
sepals and petals slenderly aristulate. 35. S. Tracyi. 
Scapes 1-1.5 mm. wide: perianth less than 10 mm. long, the 
sepals and petals short aristulate. 36. S. scoparium. 
b. Plants in finally depressed assurgent or weakly diffuse tufts. 
Perianth less than 6 mm. long: capsules oblong: plants branched 
and leafy-bracted from the base. 37. S. minus. 
Perianth over 8 mm. long: capsules subglobose. 
Leaf-blades 5-7 mm. wide: scape broadly thin-winged. 38. S. colubriferum. 
Leaf-blades 0.5-3 mm. wide: scape narrowly margined. 
Plants in depressed or ascending more or less rosulate tufts : 
scapes stiff, the outer ones geniculate below. 
Perianth reddish purple: capsules pale, about 3 mm. high: 
plants not discoloring when dry. 39. S. rosulatum. 
Perianth blue: capsules dark, becoming 6 mm. high : plants 
dark when dry. 40. S. Helleri. 
Plants in weakly diffuse finally spreading or reclining tufts. 
Leaf-blades extremely slender, 1 mm. wide or less: pedun- 
cles much shorter than the scapes: plants pale and : 
glaucescent. 41. S. implicatum. 
Leaf-blades 1-3 mm. wide: peduncles very slender, mostly 
as long as the scapes or nearly so: plants deep green, 
drying dark. 42. S. flaccidum. 
c. Plants erect: species trans-Mississippian, or essentially so. 
Sides of the leaf-blades and the scapes scabrellous : pedicels slend- 
erly flexuous. 43. S. pruinosum. 
Sides of the leaf-blades and the scapes smooth (except sometimes in 
no. 49): pedicels not widely flexuous. 
Plants tall and stiff, becoming 50 em. high: peduncles terminal, 
very long and slender: capsules 6-7 mm. high or more. 44. S. longipedunculatum. 
Plants lower, from 5 cm. to rarely over 30 cm. tall: terminal 
peduncles never elongated : capsules less than 5 mm. high. 
Plants very stiff and glaucous: scapes and leaf-blades 1.5-4 
mm. wide, their edges normally rough-serrulate. 45. S. ensigerum. 
Plants never very rigid and glaucous: scapes and leaf-blades 
not strongly serrulate when over 2 mm. wide. 
Braets of the spathe closely and delicately many-nerved : 
plants 5-30 em. tall. 
Leaf-blades mostly over 2 mm. wide: plants 15-30 cm. 
Un 
. NANUM. 
tall. 
Foliage glaucous to glaucesent: perianth light blue: 
pedicels exserted. 46. S. varians. 
Foliage green to glaucescent: perianth deep blue- 
purple: pedicels scarcely exserted. 47. S. amoenum. 
Pear more less than 2 mm. wide: plants 5-20 
em. tall. 
Plants bright or light green, becoming darkened 
when dry, the tufts mostly loose and apon: 
Scapes rigid, somewhat curved: perianth bright 
blue: ovary glabrous. 48. S. Brayi. 
Scapes straight, not rigid: perianth deep purple- 
blue or pale blue: ovary puberulent. 
Leaves shorter than the ee flowers dee 
purple-blue : staminal column 1⁄4 the length 
of the perianth or less. 49. S. furcatum. 
Leaves equalling the scapes: perianth le 
blue: staminal column 2 the length of the * 
perianth or more. 50. S. Langloisii. 
Plants pale and glaucescent, not becoming dark when 
dry, relatively small and closely tufted. 
Leaf-blades 1-2 mm. wide: perianth pale violet- 
blue: staminal column 4-6 mm. high: ovary E 
puberulent to glabrate. 51. S. Bushii. 
Leaf-blades about 0.5 mm. wide: perianth bright 
purplish blue: staminal column 3 mm. high: 
ovary glabrous. 52. S. Canbyi. 
Braets of the spathe thickened, strongly rather few-nerved, 
the spathes becoming somewhat thickened. 58. S. Teranum. 
