PURSLANE FAMILY 131 



3. Calyptridium rdseum S. Wats. Rosy Calyptridium. Fig. 1642. 



Calyptridium roseum S. Wats. Bot. King Expl. 44. 1871. 



Depressed or spreading annuals with branches varying from 2 to 10 cm. in length. Leaves 

 few, spatulate, 2-5 cm. long, basal and scattered along the branches ; inflorescence paniculate, the 

 branches with short, peduncled scorpioid clusters ; sepals asymmetrical, somewhat accrescent, 

 the larger 4 mm., the smaller 2 or 3 mm. long, orbicular with a broad scarious margin, white or 

 tinged with pink; petals 2, small; stamen 1, not surpassing the petals; style 0.5 mm. long or less, 

 2-parted and with a subcapitate stigma; capsule ovate-oblong, shorter than the calyx, 6-15-seeded. 



Alkaline valleys of the Great Basin region, Upper Sonoran Zone; eastern Oregon and Wyoming to Inyo 

 County, California, and central Nevada. Type locality: Monitor Valley, Nevada. June-July. 



4. Calyptridium quadripetalum S. Wats. Four-petaled Calyptridium. 



Fig. 1643. 



Calyptridium quadripetalum S. Wats. Proc. Amer. Acad. 20: 336. 1885. 



Calyptridium tetrapetalum Greene, Fl. Fran. 182. 1891. 



Annual, erect or ascending from a decumbent base with branches 2-10 cm. long. Leaves basal 



and cauline, oblong, spatulate, 5-30 mm. long ; inflorescence dense, 2-4 cm. long, scorpioid ; sepals 



round-reniform, white or pink, scarious, 3-4 mm. long ; petals 4, ovate, 2 mm. long ; stamens 2-3, 



style very short ; capsule oblong-oval, 10-20-seeded. 



In open places, Upper Sonoran Zone; Inner Coast Ranges from Glenn County to Sonoma County, California. 

 Type locality: Lake County, California. June. 



7. LEWISIA Pursh, Fl. Amer. Sept. 368. 1814. 



Glabrous perennial from a globose corm or fleshy root with a short caudex and stems 

 jointed at the base or below the inflorescence. Basal leaves entire, enlarged at the base of 

 the petiole, the widened base mostly hyaline. Stem leaves few, often bract-like. Inflo- 

 rescence bracteate, 1-40-flowered, sometimes readily disjointing in age. Flowers perfect, 

 soon withering. Petals 4—18, often unequal in width and sometimes in length. Sepals 2-6, 

 persistent. Stamens 5 to many with versatile anthers and slender filaments often united 

 at the base. Styles 3-8, united at the base. Capsule globose or ovoid, in most cases thin- 

 walled, circumscissile at the base, then splitting towards the apex. Seeds 6-70, rarely as 

 few as 3, black or dark brown, shining, finely granulate with low tubercles to very smooth. 

 [Name in honor of Meriwether Lewis of the Lewis and Clark Expedition.] 



A genus of about 18 species, native of western North America. Type species, Lewisia rcdiviva Pursh. 



Basal leaves absent or solitary. 1. L. triphylla. 



Basal leaves present, many. 



Petals 2.5 cm. or more long; seeds with a conspicuous aril. 2. L. Tweedyi. 



Petals less than 2 cm. long; seeds without an aril. 



Stems 11-35 cm. high, much exceeding the basal leaves. 



Stem leaves similar to the basal; stamens many. 3. L. oppositifolia. 



Stem leaves bract-like; stamens less than 10. 



Flowers with stout pedicels; petals 10-17 mm. long. 4. L. Cotyledon. 



Flowers with slender pedicels; petals 6-10 mm. long. 



Basal leaves terete or nearly so; branches of the inflorescence divaricate. 



5. L. Leana. 



Basal leaves flattened; branches of the inflorescence ascending. 6. L. columbiana. 

 Stems short, scarcely if at all surpassing the leaves. 



Bracts remote from the sepals and dissimilar to them. 



Sepals herbaceous or scarious; inflorescence not disjointing in fruit. 



Sepals glandular-toothed, veins conspicuous in age. 7. L. pygmaea. 

 Sepals entire or if obscurely few-toothed then not glandular. 



Petals white, 8-12 mm. long. 8. L. nevadensis. 



Petals pink or red, 3-4 mm. long. 9. L. sierrae. 



Sepals petaloid, becoming scarious throughout; inflorescence readily disjointing in fruit. 



Sepals 6; bracts 5-8, subulate. 10. L. rediviva. 



Sepals 2; bracts 1-3, ovate. 11. L. disepala. 

 Bracts immediately below the sepals and similar to them. 



Bracts entire. 12. L. brachy calyx. 



Bracts glandular-denticulate. 13. L. Kelloggii. 



1. Lewisia triphylla (S. Wats.) Robinson. Three-leaved Lewisia. Fig. 1644. 



Claytonia triphylla S. Wats. Proc. Amer. Acad. 10: 345. 1875. 

 Oreobroma triphyllum Howell, Erythea 1 : 33. 1893. 



Lewisia triphylla Robinson in A. Gray, Syn. Fl. N. Amer. I 1 : 269. 1897. 

 Eriocallis triphylla Rydb. Bull. Torrey Club 33: 140. 1906. 



Perennial from a deep-seated corm with 1-5 slender stems 3-11 cm. high. Basal leaves none 

 at flowering time; cauline leaves 2-4, linear, 2.5-5 cm. long, opposite or verticillate, subtending 

 the inflorescence; inflorescence bracteate, umbellate, sometimes branching; flowers 3-15, rarely 

 1-2; sepals oval, entire, 3-4 mm. long; petals white or pink, 5-8, 4-5.5 mm. long; capsule mem- 

 branous, ovate, 3-4 mm. high ; seeds 10-25, dark, shining. 



Common in sandy or gravelly soil, Transition and Canadian Zones; mountain ranges of Washington south 

 to the southern Sierra Nevada, California, and east to the Rocky Mountains. Type locality: Cisco, California. 

 June— Aug. 



