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 miich shorter than the straight wiug-flattened 



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



Leaves equalling the fiexuous subterete scapes : capsules 



4-Gmm. high. 32. S. flexile. 



Plants 15-30 cm. tall, somewhat stiff or rigid. 



Perianth becoming 1.5 mm. long: staminal column 5 

 mm. high : bracts of the spathe finely puncticulate- 

 dotted. 33. S. fiolaceum. 



Perianth about 10 mm. long : staminal column 4 mm. 



high or less : bracts of the spathe not dotted. 34. S. 7>anum. 



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'. scopariiim. 



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. rosulahtm. 



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



dark when dry. 40. .S'. Helleri. 



Plants in weakly ditliise 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 tran,s-Mississippian, or essentially so. 



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

 • erlv flexuous. 43. S. pruinosum. 



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

 no. 49): pedicels not widely fiexuous. 

 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 stift' and glaucous : scapes and leaf-blades 1..5-4 



mm. ^vide, 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 .5-130 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. 48. S. Brayi. 



Scapes straight, not rigid : perianth deep purple- 

 blue or pale blue : ovary puberulent. 

 Leaves shorter than the scapes : flowers deep 

 purple-blue : staminal column 3^ 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 

 putjerulent to glabrate. 51. S. Busltii. 



Leaf-blades about 0.5 mm. wide : perianth bright 

 purplish blue : staminal column 3 mm. high : 

 ovary glabrous. 52. S. Canbyi. 



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



the spathes becoming somewhat thickened. 53. S. Texanum. 



44. S. longipedunculatum. 



45. .S'. cndgerum. 



S. varians. 

 S. amoenum. 



49. 



50. 



S. furcatum. 

 S. Langloisii. 



