KOEBERLINIACEAE 671 



Fruit subglobose, pubescent, separating into 5 carpels. Seeds solitary in eacb carpel. 

 CREOSOTE BUSH. 



1. Covillea tridentata (Cav. ) Vail. A diffuse shrub, 0.5-3 m. tall, finely pubes- 

 cent throughout. Leaves numerous, excreting a resinous heavy-scented gum : leaflets 2, 

 the blades leathery, oblong-ovate, 6-12 mm. long, inequilateral, acute, sessile : sepals 5, 

 obovate, concave, 5-6 mm. long, finely pubescent : corolla bright yellow, nearly 2 cm. 

 broad : petals 5, oval-obovate, about 10 mm. long, crisped and undulate at the apex ; blades 

 narrowed into short claws : ovary densely bristly-pubescent, separating into 5 indehiscent 

 carpels. 



On plains and prairies, Utah and Nevada to Texas, Arizona and Mexico. Spring to fall. 



4. GUAIACUM L. 



Shrubs or trees, with a pale, scaly bark and an exceedingly hard wood pervaded by a 

 dark colored gum-resin. Leaves opposite, sometimes apparently fascicled : stipules small. 

 Flowers irregular, on terminal peduncles. Sepals 5, or rarely 4, imbricated, unequal, 

 deciduous. Disk inconspicuous or elevated. Petals blue or purple, 5 or rarely 4, imbri- 

 cated, more or less clawed. Stamens 10, inserted on the disk : filaments filiform, naked : 

 anthers cordate or sagittate. Ovary short-stalked, 2-5-celled, 2-5-angled : stigma entire 

 or minutely 2-5-toothed. Ovules 8-10 in each cavity, pendulous, anatropous. Fruit 2-5- 

 angled or winged, at maturity separating into 2-5 leathery carpels. Seeds solitary, with a 

 thick fleshy testa. Endosperm horny-cartilaginous. LIGNUM-VITAE. 



1. Guaiacuxn sanctum L. An evergreen shrub, or a small tree, sometimes 10 m. 

 tall : trunk rarely 1 m. in diameter, clothed with a very pale or white bark : branches 

 forking : leaves 5-10 cm. long, becoming glabrous : leaflets 6-8, the blades oblong or 

 obovate, 2-3 cm. long, usually apiculate, entire, inequilateral, sessile : flowers terminal on 

 solitary or clustered pedicels, which are shorter than the subtending leaves : sepals 5, 

 obovate or oblong-obovate, 6-7 mm. long, concave, often ciliate : corolla blue, about 2.5 

 cm. wide : petals 5, broadly obovate, cuneately narrowed below, twisted near the base, 

 spreading : filaments glabrous, dilated at the base : ovary glabrous : fruit obovoid, 15-17 

 mm. long, 5-angled, orange-colored : seeds elliptic, covered with a scarlet aril. 



In sand, Florida Keys. Also in the Bahamas and the West Indies. 



5. PORLIERIA K. & P. 



Rigid spreading shrubs. Leaves opposite: leaflets opposite, with narrow entire 

 blades : stipules sometimes spine-like. Flowers terminal on clustered or solitary pedicels. 

 Sepals 4-5, imbricated, broad, deciduous. Petals 4-5, imbricated, short-clawed, surpassing 

 the sepals. Stamens 8-10 ; filaments filiform, each with a 2-cleft or cut scale below the 

 middle : anthers becoming incurved. Ovary 2-5-celled, sessile or slightly immersed in 

 the disk, 2-5-ribbed. Ovules 4 in each cavity, superposed in pairs. Fruit subglobose or 

 obovoid, 2-5-lobed, 2-5-celled. Seeds solitary in each cavity. Testa fleshy. Endosperm 

 hard. 



1. Porlieria angustifolia (Engelm.) A. Gray. A shrub or small tree, 1-7 m. tall, 

 with spreading or straggling branches. Leaves 1.5-2 cm. long, glabrous : leaflets 8-12, 

 the blades linear, 0.5-1.5 cm. long, reticulated, apiculate, entire or slightly crenate above, 

 oblique at the base, sessile : flowers purple, about 12-20 mm. broad : sepals suborbicular, 

 concave, 5 mm. long : petals nearly elliptic, 1 cm. long, lilac, often notched at the apex : 

 filaments pink : anthers bright yellow : ovary pubescent : capsule nearly 2-lobed, 2 cm. in 

 diameter, reticulated. 



On plains or prairies, Texas and Mexico. Spring and summer. 



FAMILY 6. KOEBERLINIACEAE Engler. JUNCO FAMILY. 



Very much branched, nearly leafless Texano-Mexicau shrubs or trees, with 

 a red-brown scaly bark, the branches terete, the branchlets pale-green, ending 

 in straight or curved rigid spines. Leaves scale-like, alternate, broadest above 

 the middle, caducous. Flowers small, perfect, in short racemes near the ends 

 of the branchlets. Calyx of 4 or rarely 3, distinct, imbricated sepals, deciduous. 

 Disk obsolete. Corolla of 4 or rarely 3 white, convolute, somewhat clawed 

 petals. Androecium of 8 stamens, inserted under the ovary. Filaments nar- 



