IXIACEAE 



295 



40. S. Helleri. 



41. S. implicatum. 



Inflorescence scant, with 1 or sometimes 2 nodes, each bearing 1 or 2 peduncles. 

 Plants mostly over 30 cm. tall, when lower very delicate arid slender. 

 Leaves much shorter than the straight wing-flattened 



scapes : capsules 2-4 ram. long. 31. S. Atlanticum. 



Leaves equalling the flexuous subterete scapes : capsules 



4-6 mm. high. 32. S. flexile. 



Plants 15-30 cm. 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. 34. S. nanum. 



Inflorescence more contracted and compound, mostly with 2-4 



nodes each bearing 2-4 peduncles. 

 Scapes 1.5-3 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. rosulalum. 



Perianth blue : capsules dark, becoming 6 mm. high : plants 



dark when dry. 



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. 



Leaf-blades 1-3 mm. wide : peduncles very slender, mostly 

 as long as the scapes or nearly so : plants deep green, 

 drying dark. 



c. Plants erect : species trans-Mississippian, or essentially so. 



Sides of the leaf-blades and the scapes scabrellous : pedicels slend- 

 erly flexuous. 

 Sides of the leaf-blades and the scapes smooth (except sometimes in 



no. 49 ) : pedicels not widely flexuous. 

 Plants tall and stiff, becoming 50 cm. high : peduncles terminal, 



very long and slender: capsules 6-7 mm. high or more. 

 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. 

 Plants never very rigid and glaucous : scapes and leaf-blades 



not strongly serrulate when over 2 mm. wide. 

 Bracts of the spathe closely and delicately many-nerved : 



plants 5-30 cm. tall. 

 Leaf-blades mostly over 2 mm. wide : plants 15-30 cm. 



tall. 

 Foliage glaucous to glaucesent : perianth light blue : 



pedicels exserted. 



Foliage green to glaucescent : perianth deep blue- 

 purple : pedicels scarcely exserted. 

 Leaf-blades mostly less than 2 mm. wide: plants 5-20 

 'cm. tall. 

 Plants bright or light green, becoming darkened 



when dry, the tufts mostly loose and open. 

 Scapes rigid, somewhat curved : perianth bright 



blue : ovary glabrous. 



Scapes straight, not rigid : perianth deep purple- 

 blue or pale blue : ovary puberulent. 

 Leaves shorter than the scapes : flowers deep 

 purple-blue : staminal column % the length 

 of the perianth or less. 



Leaves equalling the scapes: perianth pale 

 blue : staminal column % the length of the 

 perianth or more. 

 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 

 puberulent to glabrate. 



Leaf-blades about 0.5 mm. wide : perianth bright 

 purplish blue : staminal column 3 mm. high : 

 ovary glabrous. 



Bracts of the spathe thickened, strongly rather few-nerved, 

 the spathes becoming somewhat thickened. 



43. S. pruinosum. 



44. S. longipedunculaium. 



45. S. ensigerum. 



46. S. varians. 



47. S. amocnum. 



48. S. Brayi. 



49. S.furcatum. 



50. S. Langloisii. 



51. S. Bushii. 



52. S. Canbyi. 



53. S. Texanum. 



