LEGUMINOS. 
SILVA OF NORTH AMERICA. 
125 
ACACIA GREGGII. 
Cat’s Claw. Una de Gato. 
LEGUMES narrow, often conspicuously contracted between the seeds; seeds nearly 
orbicular. Leaves hoary pubescent. 
Acacia Greggii, Gray, Smithsonian Contrib. ii. 65; v. 53 
(Pl. Wright. i., ii.) ; Ives’ Rep. 11. — Torrey, Sitgreaves’ 
Rep. 158.— Torrey, Pacific R. R. Rep. vii. pt. iti. 10; 
Bentham, Trans. Linn. Soc. xxx. 521 (Rev. Mim.).— 
Brewer & Watson, Bot. Cal. i. 164.— Rothrock, Wheeler’s 
Rep. 108. — Hemsley, Bot. Biol. Am. Cent. i. 353. 
Bot. Mex. Bound. Surv. 61.— Walpers, Ann. iv. 625. — 
A low many-branched tree, rarely thirty feet in height, with a trunk ten or twelve inches in 
diameter ; or often a straggling shrub. The bark of the trunk is an eighth of an inch thick and 
The branches are armed with stout recurved 
The branchlets 
are striately angled, puberulous, and pale brown faintly tinged with red. The leaves are alternate on 
furrowed, the surface separating into thin narrow scales. 
infrastipular terete spines a quarter of an inch long, and broad and flat at the base. 
the young branchlets and fascicled in the axils of earlier leaves, pubescent or puberulous, with two to six 
pinne, one to three inches in length, persistent and petiolate, the short slender petioles being furnished 
near the middle with a minute oblong chestnut-brown gland; the pinne are eight to ten-foliolate, 
with oblique obovate hoary leaflets rounded or truncate at the apex, and unequally contracted at the 
base into short petiolules; they are two or three-nerved, reticulate-veined, from a sixteenth to a quarter 
of an inch long, and rather thick and rigid. The stipules are linear, acute, a sixteenth of an inch long, 
and caducous. The flowers, which appear in succession from April to September, are produced in dense 
oblong pubescent spikes from the axils of minute caducous bractlets; they are fragrant, bright creamy 
yellow, and with their stamens nearly a quarter of an inch long. The peduncles vary from one half to 
two thirds of an inch in length, and are fascicled usually two or three together in the axils of the leaves 
towards the ends of the branches. The calyx is obscurely five-lobed, puberulous on the outer surface, 
and half as long as the petals, which are only slightly united at the base and are bordered with a narrow 
margin of pale tomentum. The ovary is long-stalked and clothed with long pale hairs. The legumes, 
which are fully grown in midsummer, hang unopened on the branches until winter, and sometimes until 
the following spring; they are narrow, compressed, straight or shghtly falcate, obliquely contracted at 
the base into a short stalk, and acute or rounded at the apex; they are more or less contracted between 
the seeds, and when fully ripe are curled or often contorted; the valves are thin and membranaceous, 
thick-margined, light brown, and conspicuously transversely reticulate-veined. The seeds are nearly 
orbicular, compressed, and a quarter of an inch in diameter ; the testa is thin, crustaceous, dark brown 
and lustrous, and marked on the two sides of the seed with a small oval depression. The embryo is thin, 
with a short included radicle.’ 
Acacia Greggii is distributed from the valley of the Rio Grande in western Texas through southern 
1 Acacia Greggii often resembles Acacia Wrightii so closely that ally pubescent. The pods are narrower and more conspicuously 
it is not easy to distinguish the two trees. Bentham described the 
Texas plant as unarmed, and depended chiefly upon this character 
contracted between the seeds, and when fully ripe become twisted 
and contorted, a peculiarity I have never seen in the pods of Acacia 
to separate the two species. The branches of Acacia Wrightit, 
however, are armed, and it is unusual to find them without the 
short recurved spines which are similar on the two species. The 
leaflets of Acacia Greggii are rather smaller than those of Acacia 
Wrightii, and the foliage is a much lighter green and more gener- 
Wright. The seeds, however, offer the best means for distinguish- 
ing the species. In Acacia Wrightit they are narrowly obovate or 
ovate, and in Acacia Greggu are constantly orbicular or nearly so, 
and much larger. 
