Part 1, 1907] I.IXACEAE 69 



5. Linum pratense (J. B. S. Norton) Small. 



Linum Leunsii pratense J. B. S. Norton, Trans. Acad. St. Louis 12 : 38. 1902. 



Plants perennial, 1-6 dm. tall, the stems commonly branched at the base, striate in 

 age ; leaves mainly ascending, commonly numerous and rather crowded on the lower part 

 of the stem, the blades narrowly linear to linear-subulate, 0.5-1 cm. long, or sometimes 

 slightly longer, more or less involute, rather succulent; bracts subulate; pedicels 0.5-1.5 

 cm. long at maturity and then curved at the base; sepals mostly 4-5 mm. long at maturity, 

 the outer ovate to oblong-ovate, acute or short-acuminate, the inner broader than the outer, 

 usually mucronulate, all eciliate ; petals blue, 1-1. 5cm. long, mostly less than 1.5cm. long; 

 styles distinct or slightly united at the base ; capsules similar to those of Linum Lewisii in 

 shape, but less than twice as long as the sepals, the septa ciliate ; seeds about 4 mm. long. 



Type locality : Kearney County, Nebraska. 

 Distribution : Saskatchewan to'Texas and Arizona. 

 Illustration : Trans. Acad. St. Louis 12 : pi. 6. 



2. CATHARTOLINUM Reichenb. Handb. 307. 1837. 



Linopsis Reichenb. Handb. 307. 1S37. 



Mesynium Raf. Fl. Tell. 4: 33. 1838. 



tNezera Raf. New Fl. 4: 64. 1838. 



Alsolinum Fourr. Ann. Soc. Linn. Lyon II. 16: 349. 1868. 



Chi vsolinum Fourr. Ann. Soc. Linn. Lyon II. 16 : 349. 1S68. 



Leucolinum Fourr. Ann. Soc. Linn. Lyon II. 16 : 349. 1868. 



Annual or perennial often paniculately or corymbosely branched herbs. Leaves alter- 

 nate or occasionally opposite, without stipules but sometimes with stipular glands ; blades 

 mostly narrow, entire or serrulate, sometimes ciliate or glandular-margined. Sepals 5, 

 persistent or deciduous, all of them or only the inner ones with gland-tipped teeth. Petals 

 5, yellow or white, unappenaged but sometimes pubescent within near the entire base. 

 Stamens 5 ; filaments united at the base, the free portion, abruptly or gradually dilated at 

 the base, not accompanied by staminodia or rarely with a short staminodium in each sinus. 

 Gynoecium 5-carpellary, or rarely 2-carpellary, sometimes cartilaginous at the base ; styles 

 filiform, distinct or united; stigmas distinct, terminal, capitate. Capsule ovoid or de- 

 pressed, 5-celled, or rarely 2-celled, and with firm septa, or completely or incompletely 

 10-celled by false septa, the carpels not ribbed on the back. Seeds flattened, often lunate. 



Type species, Linum catharticum L. 



Styles distinct. 



Staminodia wanting. 



Petals not auricled at the base ; flowers borne in panicled or corym- 

 bose cymes. 

 Petals auricled at the base ; flowers borne in fastigiate corymb-like or 

 virgate raceme-like cymes. 

 Staminodia present. 



Stipular glands wanting ; corolla white. 



Staminodia 2-lobed ; sepals keeled on the back ; flowers short- 



pedicelled. 

 Staminodia subulate ; sepals not keeled ; flowers loug-pedicelled. 

 Stipular glands present ; corolla yellow. 

 Styles more or less united. 



Inner sepals, at least, with glandular-toothed margins, or rarely entire. 

 Sepals persistent ; capsules without thickenings at the base. 

 Sepals deciduous ; capsules with cartilaginous thickenings at the base. 

 Inner and outer sepals with broad scarious erose -ciliate margins. VIII. Multicaulia. 



I. VlRGINIANA. 



Sepals entire at maturity, the inner ones sometimes erose on account of 

 the bases of the deciduous glandular hairs. 

 Outer sepals 2-2.5 mm. long at maturity ; stems paniculately branched. 1. C. striatum. 

 Outer sepals 3-3.5 mm. long at maturity ; stems eorynibosely branched. 2. C. virginianum. 

 Sepals, either those of the inner series, or of the outer, or of both series, 

 glandular-toothed. 

 Capsules spheroidal. 



Outer sepals typically lanceolate ; inner sepals abruptly long- 

 pointed. 3. C. medium. 

 Outer sepals typically ovate ; inner sepals acute or abruptly short- 

 pointed. 4. C. Curtissii. 

 Capsules ovoid. 



