IRIDACEAE. 285 



Flowers from terminal spathes consisting of mostly one pair of opposite condupli- 

 catc herbaceous bracts enclosing membranous scales; perianth blue, violet, or white 

 with a yellow eye, rarely all yellow, the 6 oblong orobovate segments spreading and 

 anstulate; filaments monadelphous ; anthers linear or oblong, the sacs distinct at 

 base; style threadform, the branches filiform or obsolete; ovary 3-celled; capsule 

 globose, oval or obovoid, usually trigonous, loculicidally 3-valved; seeds globose to 

 obovoid, often angled, pitted or smooth. Flowers fugacious, opening successively 

 in sunlight, each usually lasting but a day. Probably not less than 125 species, 

 nearly all American. Besides the following many others occur in the Southern 

 and Western States. 



Filaments free above, anthers over 3.5 mm. long ; spathes twin, sessile, terminating the 



subterete wingless stem. i. S. hostile. 



Filaments monadelphous to the top; anthers under 2.5 mm. long. 



Spathes twin, sessile, terminating the winged stem. 2. S. albidum. 



Spathes single. 



Flowers yellow ; primary bract long and foliaceous, stem simple. 



4. S. flaviflorum. 

 Flowers blue, violet or white. 



Stems mostly simple with a sessile terminal spathe. 



Capsules 4-6 mm. high, leaves 2-6 mm. wide. 6. S. angustifolium. 



Bracts glabrous, the outer one united-clasping below, flowers deep 

 violet blue, rarely T ,vhite. 5. S. mucronatum. 



Capsules 2-4 mm. high, leaves 0.5-2 mm. wide. 



Bracts scabrous, puberulent, sometimes glabrous, the outer one not 

 united-clasping at base or scarcely so ; flowers pale blue or white. 



3. 6". campestre. 

 Stems both simple and branched, broadly winged; spathes mostly purplish. 



7. S. intermedium. 

 Stems mostly branched above, bearing two or more pedunculate spathes. 



Tufts fibrose-coated at base. 



Plant turning dark when dry ; capsules dark and thick-walled ; pe- 

 duncles mostly over i mm. wide ; coastwise. 



8. S. arenicola. 

 Plant not turning dark when dry ; capsules pale and thin-walled ; 



peduncles mostly under 0.5 mm. wide. 9. *$". Farwellii. 



Tufts not fibrose-coated at base. 



Plant usually turning dark in drying ; stem broadly winged ; 



pedicels spreading or recurved. 10. S. graminoides. 



Plant not turning dark when dry; pedicels not recurved; spreading. 

 Capsules dark and thick-walled, 



Spathes 13-20 mm. long; capsules longer than broad, not 



apiculate; inner bract obtuse. n. S. Atlanticum. 



Spathes 10-13 mm. long; capsules broader than long, 



apiculate. 12. S. apiciilatum. 



Capsules pale and thin-walled; peduncles closely erect; inner 

 bract acute. 13. 6". strictum. 



1. Sisyrinchium hastile Bicknell. SPEAR-LIKE SISYRINCHIUM. Very slen- 

 der and stiffly erect, dull green, 3-4 dm. high. Stems I mm. 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 2-2.5 cm - l n g> 

 primary bract slenderly much prolonged ; interior scales ample, sometimes slightly 

 exserted ; flowers few, on pedicels not longer than the inner bracts. Fruit and 

 color of flower unknown. Sandy shores of Belle Isle in the Detroit River, Mich. 

 Early June. 



2. Sisyrinchium albidum Raf. WHITE BLUE-EYED GRASS. Green and glau- 

 cescent, the spathes often purplish, 1.5-4.5 dm. high. Leaves half the height of 

 the stems or longer, 1-3.5 mm - wide, very acute, mostly smooth-edged ; stems 

 usually broadly winged, 1-3 mm. wide, the edges serrulate to smooth ; spathes 

 sessile in a close terminal pair, the prominent outer bract 2.5-7 cm. long, its edges 

 free to the base; inner bracts acuminate, often ciliolate on the keel, mostly 15-20 

 mm. long; flowers white to pale blue; perianth 8-12 mm. long; capsules pale, 

 depressed- subglobose, 2-3 mm. high, on erect-spreading pedicels usually shorter 



