446 



LILIACEAE 



41. Calochortus obispoensis Lemmon. Lemmon's }^Iariposa. Fig. 1097. 



Calochortus obispoensis Lemmon, Bot. Gaz. 11: 180. 1886. 

 Calochortus weedii obispoensis Purdy, Proc. Calif. Acad. III. 2: 

 133. 1901. 



Stems simple or branched, from a deep-seated 

 coarsely fibrous-coated bulb. Leaves linear, long- 

 attenuate ; flowers usually several terminating the race- 

 mose branches ; sepals lanceolate, long-acuminate, 20 

 mm. long", orange within; petals oblong-ovate, 10-15 

 mm. long, deep orange, tinged with brown, ciliate 

 on the margin, the region of the gland covered with 

 long spreading orange-colored hairs, forming a con- 

 spicuous tuft, upper half of petal but sparsely hairy; 

 stamens equalling the petals ; filaments slender, 8 mm. 

 long; capsule linear-lanceolate, attenuate at apex. 



Rocky hillsides, Upper Sonoraii Zone; San Luis Obispo 

 County. Type locality: on dry stony hills, Steele's Ranch, near 

 San Luis Obispo, California. 



22. YUCCA L. Sp. PI. 319. 1753. 



Acaulescent or arborescent plants with a woody simple or branched caudex, and soft or 



usually rigid leaves, entire, minutely denticulate or hliferous on the margins. Flowers in 



large panicles, " their perianth-segments open-campanulate to incurved, thin or thickish. 



Stamens 6, filaments enlarged above ; anthers versatile. Stigmas sessile or on a short 



style; 6-lobed or notched, with the stigmatic surface on the wall of the central cavity. Fruit 



a dehiscent loculicidal capsule, or indehiscent and dry and spongy, or fleshy and berry-like. 



Seeds numerous, thin and flat, usually lustrous black. [The Haytien name.] 



An American genus of about 30 species. Most abundant in southwestern United States and the Me.xican 

 Plateau region. Pollination is affected by the Yucca moth, which deposits its eggs in the cavities of the ovary 

 and then places pollen within the stigmatic tube of the stigma. Type species, Yucca aloifolia L. 



Leaves minutely denticulate; perianth-segments more or less incurved; stigma sessile; fruit dry and spongy. 



1. Y. brevifolia. 



Leaves filiferous on the margin; perianth-segments open-camijanulate; style evident; fruit fleshy. 



Perianth-segments spreading from the base; style very short. 2. Y. niohaz'ensis. 



Perianth-segments appressed to above the ovary, then spreading; style elongated, 2-3 cm.^ long. 



3. Y. baccata. 



1. Yucca brevifolia Engelm. 



Toshna Tree. Fig. 1098. 



Yucca draconis arborescens Torr. Pacif. R. Rep. 4: 147. 1857. 

 Yucca brevifolia Engelm. Bot. King. Expl. 496. 1871. 

 Yucca arborescens Trelease, Rep. Mo. Bot. Card. 3: 163. 1892. 

 Cleisforucca arborescens Trelease, Rep. Mo. Bot. Card. 13: 43. 

 1902. 



Tree 8-12 m. high, becoming much branched and 

 forming a rounded open head, with a roughened trunk, 

 5-8 dm. in diameter, young trees unbranched until 2-3 

 m. high and clothed nearly to the ground with spreading 

 or reflexed leaves. Leaves very rigid and sharp- 

 pointed, forming large tufts at the ends of the branches, 

 spreading in all directions, 15-25 cm. long, 10-15 mm. 

 wide, more or less 3-sided, minutely denticulate ; 

 panicle sessile, 25-35 cm. long, dense, often short hispid; 

 flowers greenish white, oblong or globose; perianth-seg- 

 ments 25-30 nun. long ; fruit ovoid, 5-10 cm. long, dry 

 and spongy, indehiscent. 



One of the most striking features of the Mojave Desert, Lower 

 Sonoran Zone; Antelope Valley, Los Angeles County, California 

 to Detrital Valley, northern Arizona, and the Beaver Dam Moun- 

 tains, southern Utah. Type locality: not indicated. 



