170 DRACAENACEAE 



1 



Fruit a dry capsule. 



Leaves narrowly linear, very long. 



Style stout, swollen green. 1. y. giauca. 



btyle not swollen, white. 2 V anaustissima 

 Leaves linear-lanceolate, short; style not swollen, white. ■ ■ v 



Leaves not papillose. 3. y. Harrimaniae. 



Leaves densely rough-papillose at least on the back. 4 Y Gilbertiana 



Fruit fleshy. 



'6. Y. baccata. 



1. Y. glauca Nutt. Subacaulescent or branching with decumbent stems; 

 leaves rigid, 6-12 mm. wide, 2-4 dm. long, white-margined, finely but sparingly 

 hliferous; inflorescence 1-2 m. high, simple or somewhat branched; sepals and 

 petals greenish white, oval to lanceolate, acute, 4r-5 cm. long; capsule oblong, 

 usuaUy not constricted, somewhat roughened, brown. Y. angustifolia Pursh. 

 riains and hiUsides: la.— Tex.— Ariz.— Mont. Plaiyis—Suhmont. My-Jl. 



2. Y. angustissima Engelm. Acaulescent, with a thick horizontal root- 

 stock- leaves 2-4 dm. long, 2-5 mm. wide, pungent, white-margined, very freely 

 curly-hliferous ; inflorescence 1-1.5 m. high, racemose, or short-branched below; 

 sepals and petals rather short, lanceolate, acute; capsule scarcely 5 cm. long, 



rough, brown, constricted in the middle. Desert regions: Ariz.— s Utah. L. 

 oon. 



3. Y. Harrimaniae Trelease. Acaulescent, often cespitose; leaves linear to 



lanceolate, 6-40 mm. wide, rigidly spreading, glaucous or green in age, pungent, 



narrowly brown-margined, with coarse curled fibers; inflorescence 2.5-5 dm. high, 



sunple; sepals and petals greenish, oval, obtuse or acute; capsule brown, broadly 



oblong about 4 cm. long, constricted. Drv regions: Utah— w Colo.— w N.M. 

 oon. Je. 



4. Y. Gilbertiana (Trelease) Rydb. Acaulescent; leaves linear, about 4.5 

 dm long, 2 cm. wide, openly concave, glaucous at least on the upper side, pun- 

 gent, tibrous-falamentose on the margin; flowers about 4 cm. long; segments nar- 

 row acute; ovary- papillate; style oblong, pale. Y. Harrimaniae Gilbertiana 

 1 release. Dry regions: w Utah. Au. 



6. Y. baccata Torr. Low, usually with stout prostrate branched caudex; 

 leaves rigid, spreading, about 6 dm. long and 5 cm. wide, concave, shagreen- 

 roughened, w-ith narrow brown margins, coarsely filiferous; sepals and petals 

 lanceolate, about 7.5 cm. long; style slender, elongate; fruit large, sometimes 

 Z dm. long, oblong- or conical-ovoid, pendent, fleshy. Dry plains: Tex.- 

 Colo.— Nev, Son.—Submont. Ap-Je. 



2. CLISTOYtJCCA (Engelm.) Trelease. Joshua Tree. 



Large tree. Leaves short, thick, not filiferous. Flowers in panicles. Sepals 



and petals each 3, thick, incurved at the end. Stamens 6, hypogynous; filaments 



thick, curved outward; anthers sagittate, horizontal. Ovary 6-celled; stigma 



sessUe, 6-lobed. Capsule 6-celled, spongy, indehiscent. Seeds numerous, flat, 

 thin. ' ' 



1. C. brevifolia (Engebn) Rydb. A tree 5-10 m. high, with rough bark; 

 leaves 1.5-2 dm. long, 6-15 mm. wide, rough, serrulate on the margin, spine- 

 tipped, concave above; flowers in senile short panicles; perianth campanulate 

 4-* cm. long, greenish white; capsule 5-7 cm. long. Yucca brevifolia Engelm 



Y. arborescens Trelease. C. arborescens Trelease. Desert regions : s Calif .—s 

 Utah — ^Ariz. Son. 



3. NOLINA Michx. 



Coarse herbs, with woody caudicea. Leaves crowded, rigid, narrow, entire 

 or serrulate, keeled, pungent-pointed. Flowers polygamo-dioecious, in open 

 panicles, feepals and petals each 3, distinct, l-ner\'ed, similar, white. Stamens 

 b, reduced to stammodia m the fertile flowers; filaments thick, short. Ovary 

 3-ceUed, abortive m the staminate flowers; styles obsolete during anthesis. 

 Ovules 2 m each cavity. Capsule dry, 3-winged, tardUy and irregularly open- 

 ing. Seeds often solitary-, thick. e= j ^ 



s 



