156 EUPHORBIACEAE. 



number and alternate with the petals; pistil 1; styles 2-5; 

 ovary 2-5-celled; fruit usually a capsule, often 4-10-celled by 

 false partitions; endosperm fleshy or none. 



218. LINUM. Flax. 



Annual or perennial herbs; bark tough and fibrous; leaves 

 alternate or opposite, sessile, entire, without stipules; flowers 

 perfect; sepals, petals, stamens and styles 5, regularly alternate 

 with each other; pistil of 5 united carpels, 5-celled, with 2 seeds 

 in each cell ; each cell divided in fruit by a false partition making 

 a 10-celled pod. 



Flowers small, yellow. L. digynum. 

 Flowers large, blue. 



Annual; stigmas as long as the styles. L. usitatissimum. 



Perennial; stigmas short. L. lewisii. 



Linum digyntun Gray. Annual, glabrous and glaucous, much branched, 

 10-15 cm. high; stems slender, striate; leaves opposite, elliptic, 5-10 ram. long, 

 the lower entire and obtuse, the upper acute and serrate; stipules none; 

 flowers in loose leafy racemes or corymbs, short-pedicelled ; sepals ovate, 

 unequal, glandular, serrate or lacerate; petals yellow, 3 mm. long, without 

 appendages; capsule a little shorter than the calyx. Rare, in springy gravelly 

 places. 



Linum usitatissimum L. Common Flax. Erect annual; stem 30-50 cm. 

 high; leaves alternate, linear-lanceolate, 2-5 cm. long; stipules none; flowers 

 in loose cymes; sepals acute, ciliate, the inner margin scarious; petals blue, 

 10 mm. long; capsule nearly indehiscent, as long as the calyx; its septa not 

 ciliate. Escaped from cultivation. 



Linum lewisii Pursh. Perennial, with a woody base, the erect branches 

 30-40 cm. high, glabrous throughout; leaves alternate, numerous, linear or 

 narrow, mostly very acute, 1-3 era. long; stipules none; flowers few, in a corym- 

 bose cyme; sepals ovate, acuminate, the inner margin scarious, usually entire, 

 4-6 mm. long; petals blue, 15-20 mm. long, obovate, without appendages; 

 filaments with slender appendages; capsule ovoid, longer than the calyx, 

 incompletely 10-celled and 10-valved. Common in low ground. 



Family 49. EUPHORBIACEAE. 



Herbs (in ours), with milky juice; leaves opposite, alternate or 

 whorled, entire or toothed, sessile or petioled; stipules present 

 or wanting; flowers monoecious or dioecious, often much reduced 

 and subtended by an involucre which resembles a calyx; parts of 

 flowers various, often different in staminate and pistillate flowers; 

 calyx none or minute; petals often wanting; stamens 1-many, 

 free or united; ovary usually 3-celled; fruit a 3-lobed capsule; 

 endosperm copious. 



