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2. ZIZYPHUS Juss, 
Spiny shrubs, with alternate leaves 3-nerved or their principal veins 
confluent toward the margin, and small flowers in umbel-like clusters. 
1. Z. obtusifolia Gray. Rigid and spinose, somewhat pubescent to glabrate: 
leaves mostly glabrate, 6 to 25 mm. long, typically thin and green, spatulate to ellip- 
tical or on long shoots ovate-deltoid, acute to emarginate, entire or the broader 
forms unequally coarse-serrate or lobed: peduncle and pedicels each about 2 mm. 
long, mostly villous like the calyx: drupe subglobose, about 8 mm. in diameter, 
black.—One of the most widespread and abundant shrubs in western and southern 
Texas, on gravelly mesas, slopes, and bluffs, and known as “lote-bush,” or “Texas 
buckthorn.” 
2. Z. lycioides Gray. Very rigid and spinose, the striate zigzag branches mostly 
velvety and whitened: leaves pale, 12 mm. long or less, short petioled, subglabrous, 
oblong or occasionally ovate, obtuse or emarginate, usually entire: drupe globose or 
somewhat elongated, about 8 mm. in diameter.—Said to occur along the Rio Grande 
in extreme western Texas, 
3. MICRORHAMNUS Gray. 
Spiny shrub, with fascicled heath-like leaves, and small solitary 
flowers. ~ 
1, M. ericoides Gray. Minutely prberulent or mostly glabrous: leaves 2 to 6 
mm. long, acute, with strongly revolute margins, the enclosed grooves densely short- 
tomentose; stipules broadly triangular, ciliate: pedicels about 2 mm. long: drupe 
oblong, 6 to 8 mm. long, the slender style disarticulating from its abruptly-pointed 
summit.—Valleys and bluffs from the Pecos westward. 
4. BERCHEMIA Neck. (SupPLe-Jack.) 
Twining shrub, with alternate slender-petioled conspicuously pin- 
nately-veined leaves, with minute flowers in rather loose panicles. 
1. B. scandens Trelease, Glabrous throughout: leaves ample, 2.5 to 5 cm. long, 
ovate, acute, or acuminate, withslightly revolute undulate margins: drupe ellipsoidal, 
about 8 mm. long: style deciduous near the base, (B. volubilis DC.)—A species of 
the Southern States and extending into Texas, where its western limit is uncertain. 
5. KARWINSEIA Zuce. (Coyorit1o.) 
Unarmed shrub, with mostly opposite pinnately-veined leaves, and 
small flowers in short peduncled axillary clusters. 
1. K.Humboldtiana Zuce. Twigs more or less puberulent: leaves inconspicuously 
pellucid-punctate and sometimes dark-dotted, slender petioled, 2.5 to 7.5 cm. long, 
elliptical-ovate, obtuse to acute or mucronate, rounded or subcordate at base, entire 
or undulate, the conspicuous mostly simple veins ending ina marginal nerve: peduncle 
few-flowered : drupe ovoid, apiculate, 12 mm. long: style articulated near the top.— 
Common on the Pecos near its mouth and thence eastward to the coast. The leaves 
are beautifully pinnate-veined, and the brownish-black berries are said to be very 
poisonous. 
6. RHAMNUS L. (BucKTHORN.) 
Shrubs or small trees (ours unarmed), with alternate or more or less 
opposite pinnately-veined leaves, and small flowers in sessile or short- 
peduncled axillary umbels, 
