662 LINACEAE 



sule 5-celled, or rarely 2-celled, septicidally 5-valved, or rarely 2-valved, or separating into 

 10 one-seeded carpels. Seeds flattened. FLAX. 



Corolla blue. 



Perennial : sepals much shorter than the capsule, the inner not ciliate : native species. 



1. L. Lewisii. 

 Annual : sepals slightly shorter than the capsule, the inner ciliate : naturalized species. 



2. L. usitatisaimum. 

 Corolla yellow. 



Styles distinct. 



Inner and outer sepals entire, sometimes erose, but not glandular-toothed. 



Stems ridged, angled or winged. 3. L. striatum. 



Stems terete or essentially so. 4. L. Virginianum. 



Inner sepals glandular-toothed, outer sepals entire or toothed. 

 Outer sepals entire : stipular glands wanting. 



Capsule spheroidal, shorter than the sepals : inner sepals with rela- 

 tively short teeth. 5. L. medium. 

 Capsule ovoid, longer than the sepals : inner sepals with relatively long 



teeth. 6. L. Horidanum. 



Outer sepals glandular-toothed : stipular glands present. 7. L. rupestre. 



Styles more or less united. 



Capsules 10-valved : styles united below the middle. 



Sepals 2.5-3 mm. long, merely acute : filaments pubescent at the base, with- 

 out interposed teeth. 8. L. Harperi. 

 Sepals 4.5-6 mm. long, slenderly acuminate : filaments not pubescent at 



the base, with interposed teeth. 9. L. sulcatum. 



Capsules 5-valved : styles united to near the apex. 



Sepals merely acuminate, serrulate or serrate, deciduous, the outer mostly 



over 5 mm. long. 

 Outer sepals 5-7 mm. long. 



Sepals with wide coarsely toothed scarious margins, the outer ovate 



to ovate-lanceolate. 10. L. marginatum. 



Sepals with narrow, finely toothed margins, the outer lanceolate to 



oblong-lanceolate. 11. L. rigidum. 



Outer sepals 8-12 mm. long. 



Inner sepals slightly shorterthan theouter, usually less than } shorter : 



leat-blades 1.5-4.5 mm. wide, acuminate. 12. L. Berlandieri. 



Inner sepals much shorter than the outer, usually over shorter : 



leaf-blades 5.5-7.5 mm. wide, mostly acute. 13.X. sanctum. 



Sepals abruptly cuspid ate-awned beyond the broad scarious ciliolate mar- 

 gin, persistent, the outer mostly less than 5 mm. long. 14. L. multicaule. 



1. Linum Lewisii Pursh. Perennial by a woody rootstock, glabrous, glaucous. 

 Stems often tufted, 2-7 dm. tall, branching above : leaves alternate, erect, or nearly 

 so, often crowded; blades linear to oblong, 0.6-2 cm. long, acute or acutish, sessile: 

 pedicels 1-2 cm. long, drooping at maturity : sepals ovate or elliptic-ovate, or oval, 5-6 

 mm. long, acute, 3-nerved, the inner not ciliate : capsule globose-ovoid, 7-9 mm. long, 

 2-3 times longer than the sepals. 



In stony or dry soil, Alaska to Manitoba, Texas and Arizona. Summer. 



2. Linum usitatissimum L. Annual, g-labrous, deep green. Stems 2-8 dm. tall, 

 simple or branching above, striate, somewhat angled above : leaves alternate, erect or as- 

 cending ; blades linear or linear-lanceolate, 1-3 cm. long, acute, sessile, 3-nerved : sepals 

 elliptic or elliptic-ovate, 5-7 mm. long, acuminate, 3-nerved at the base, the inner ciliate : 

 corolla blue, 1.2-2 cm. broad : capsules globose or depressed, 6-8 mm. long, often striate, 

 slightly surpassing the sepals : seeds flattened. 



In waste places, along railroads, more or less common throughout the civilized world. Summer. 



3. Linum striatum Walt. Perennial, bright green, more or less viscid. Stems 

 sometimes decumbent, 2-8 dm. tall, paniculately branched above, winged below the nodes 

 and angled, the branches spreading : leaves opposite, except those in or near the inflores- 

 cence ; blades thinnish, narrowly oblong or elliptic, 1-3 cm. long, acute or obtuse, sessile : 

 pedicels as long as the calyx or longer : corolla pale yellow, 6-10 mm. broad : outer sepals 

 lanceolate to oblong-lanceolate, 2-2.5 mm. long, acuminate, entire ; inner sepals ovate to 

 obovate or suborbicular, about 0.5 mm. shorter than the outer, erose-topthed near the ab- 

 ruptly pointed apex : capsules depressed-globose, 2 mm. broad, surpassing the sepals. 



In or near swamps, Ontario to Arkansas, Florida and Texas. Summer. 



4. Linum Virginianum L. Annual or perennial, glabrous, often deep green. Stems 

 2-6 dm. tall, often several together, corymbosely branched above, the branches lax, spread- 

 ing or drooping at the ends : leaves spreading or ascending ; blades thinnish, 1-3 cm. long, 

 the lower ones opposite, spatulate to oblanceolate, the upper alternate, elliptic or elliptic- 

 oblanceolate, obtuse or acute, sessile : pedicels slender, becoming longer than the sepals : 

 outer sepals lanceolate to oblong-lanceolate, 2-3.5 mm. long, entire, acuminate ; inner 

 sepals rather broader and shorter than the outer, erose-toothed near the abruptly pointed 

 apex : corolla sulphur-yellow, 10-12 mm. broad : capsules depressed, 2 mm. broad, 



' longer than the sepals or equalling them. 



In dry soil and woods, Maine and Ontario, middle Georgia and Alabama. Summer. 



