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50. ACACIA Willd. 
Shrubs or trees, often spinose or prickly, with bipinnate leaves, 
small leaflets, small flowers in globose heads or cylindrical spikes on 
axillary peduncles, numerous exserted stamens, and (usually more or 
less stipitate) pod straight or curved, thin or thick, flat or terete, 
2-valved or indehiscent. 
* Pods terete or nearly 80, indehiscent, at length pulpy or fleshy : flowers in globose heads. 
1. A. Farnesiana Willd, (Huisacugz.) A small spreading tree, with straight 
slender stipular spines, pubescent or glabrous: pinne 4 or 5 pairs; leaflets 10 to 25 
pairs, oblong-linear, crowded, 2 to 4 mm. long: pod oblong, cylindrical, and more 
or Jess acuminate, straightish or curved, at length turgid and pulpy, longitudinally 
veined and more or less nodulose, glabrous, 3.5 to 7.5 em. long, becoming 12 to 18 mm. 
thick.—From San Antonio to the Gulf coast and the lower Rio Grande. Said also 
to occur along the whole Mexican frontier. Produces a great profusion of very fra- 
graut heads of yellow flowers in February or March, The hard rose-colored wood is 
of considerable value. Very common in cultivation. 
2. A. tortuosa Willd. Very much resembling the last species and in flower read- 
ily mistaken for it, but well distinguished by the pod, which is elongated-linear, 7,5 
to 12.5 cm. long, narrow, nearly terete, curved, moniliform, flesby, and tomentose.— 
Plains of the Rio Grande near Kagle Pass. A Mexican species. 
"* Pods flat or flattish, 
+ Leaflets 10 to 50 or more pairs (rarely less in No. 5), 
3. A. Emoryana Benth. A glabrous or minutely puberulent unarmed shrub (or 
with a few minute prickles) : pinne 3 to 6 pairs; leaflets LO to 25 pairs, oblong-linear, 
strongly oblique, acutish or obtuse: flowers in oblong or cylindrical spikes, wlfich 
are more or less elongated and loosely- flowered : pod broadly-linear, flat, covered 
with a minute down, at least 7.5 em. long, and nearly 2.5 cm. broad, (A. Coulteri 
Benth.)—From the high plains near the headwaters of the Leona River to Kagle 
Pass on the Rio Grande, 
4. A. Berlandieri Benth. A cinereous-puberulent shrub, with sparse prickles or 
none: pinuxe 5 to Y pairs; leaflets 25 to 45 pairs, oblong-linear, oblique, acutish, 
veiny, 4to6 mm. long: flowers in globose heads: pod broadly-linear, usually straight, 
obtuse, narrowed at base intoa stipe, velvety-canescent with a very soft short pubes- 
cence, 10 to 15 em. long, about 2.5 em. broad, the valves perfectly flat and coriaseous 
with somewhat thickened margins. (A, tephroloba Gray.)—From the Nueces to the 
Rio Grande and west to Devil’s River; common on the dry bluffs of the lower Rio 
Grande, 
5. A. filicina Willd. A glabrous or somewhat pubescent or even hirsute unarmed 
shrub (sometimes herbaceous): pinne 2 to 15 pairs; leatlets 20 to 50 or more pairs 
(rarely but 5 to LO pairs), very small, oblong-linear, obtuse or acute, with a few scat- 
tered hairs: flowers in globose heads: pod linear, usually straight, acute or acumi- 
nate, very flat and membranaceous, with more or less sinuate margin, the reticulated 
sides impressed about the seeds, often by abortion few or even 1-seeded, pubescent 
or glabrate, stipitate, 2.5 to 5 em. long or more, 6 to 12 mm. broad, becoming red- 
dish or brown at maturity,—Throughout southern and western Texas, Apparently 
a very abundant species and exceedingly variable in its foliage and pubescence, but 
with very characteristic pods, 
+ + Leaflets 2 to 10 pairs, 
++ Flowers in globose heads, 
6. A. constricta Benth. A nearly glabrons or somewhat viscidulous shrub, with 
prominent divaricate stipular spines (straight or somewhat curved): pinnae 2 to 7 
pairs; leaflets G to 10 pairs, small (rarely over 2 mm. long), oblong, obtuse, thick, 
