49 
ries, both forming a corresponding number of samaras (fruits with 
maple-like wings). 
1. J. gracilis Gray. Stems and branches very slender, twining or trailing: leaves 
lanceolate-iinear, 2.5 cm. long, 2 to 4 mm. wide, mostly acute at both ends, the mar- 
gin with 2 or 3 tooth-like glands near the base, both surfaves (as well as the stem) 
silky with close-pressed hairs: peduncles mostly dichotomously 2-flowered; bracts 
linear, as long as the pedicels, which are minutely bibracteolate in the middle.— 
Apparently common throughout Texas south of the Colorado and west to New 
Mexico. 
ZYGOPHYLLEZ. (BrAN-CAPER FAMILY.) 
Herbs, shrubs, or trees, with Opposite pinnately compound dotless 
stipulate leaves, symmetrical 4 or 5-merous flowers solitary on lateral 
or terminal naked peduncles, stamens as many or twice as many as 
petals, and a single style terminating a 2 to 12-carpeled ovary which 
ripens dry. 
1, Tribulus. Leaves abruptly pinnate, 6 to 10-foliolate: fruit tuberculate: herbs, 
2. Larrea. Leaves 2-foliolate: fruit densely hairy: heavy-scented shrub. 
3. Guiacum. Leaves abruptly pinnate, 8 to 16-foliolate: fruit smooth, with 2 to5 
acute or wing-like angles: trees (or shrubs) with very hard wood. 
1. TRIBULUS L. 
Loosely branched hairy prostrate herbs, with abruptly pinnate op- 
posite leaves (alternate ones smaller or wanting), solitary axillary white 
or yellow flowers, 5 mostly persistent sepals, 5 fugacious petals, 10 sta- 
mens, and a lobed fruit separating from the persistent axis into 5 to 12 
indehiscent 1-seeded tuberculate or winged or spinose carpels. 
1, T. maximus L. Stems at length elongated: leaflets 3 or 4 pairs, ovate-oblong, 
6 to 12 mm, long, more or less oblique: peduncles 12 to 25 mm, long: sepals very 
hairy, linear, acuminate, 4 mm, long: petals a half longer: fruit 4 mm. high, beaked 
by a stout style about as long, the carpels roughly tuberculate. (Kallstramia maxima 
Torr. & Gray.)—Common in dry soils through southern and western Texas. 
2. T. grandiflorus Watson. Hispid with usually longer and more spreading hairs: 
leatlets 4 to 6 pairs: peduncles more elongated: sepals 6 to 12 mm. long, the petals 
usually twice longer: fruit rather more sharply tuberculate, the beak 6 to 10 mm, 
long. (Kallstremia grandiflora Torr. )—Valleys of the upper Rio Grande and its tribu- 
taries, to New Mexico. 
2. LARREA Cav. (CREOSOTE BUSH. ) 
Evergreen heavy-scented shrubs, with nodose branches, opposite 2- 
foliolate leaves, solitary yellow flowers, 5 deciduous sepals, 5-clawed 
petals, 10 stamens with filaments winged below, and a globose shortly 
stipitate densely hairy fruit of 5 indehiscent 1-seeded carpels. 
1. L. Mexicana Moric. Diffusely branched, 12 to 30 dm. high, densely leafy, of a 
yellowish hue: leaves nearly sessile, the thick resinous leaflets inequilateral, oblong, 
6 to 12 mm. long, with a broad attachment to the rhachis, somewhat curved: sepals 
ovate, obtuse, silky : petals bright yellow, 6 to 8 mm. long: fruit 5 mm. in diameter, 
beaked by the slender style-—Very common on gravelly mesas and bluffs west of the 
Pecos. The leaves are sticky with a strongly scented gum or resin, and with the 
green branches burn with a bright blaze. It has various reputed medicinal proper- 
ties. 
23204—vol, 2, No, 1——4 
