100 
nerveless: pod narrowly linear, straightish or falcate, constricted between the seeds, 
glabrous, stipitate, with coriaceous valves, 5 to 12.5 cm. long, 3 to 4 min. broad,— 
Throughout southern Texas, from the lower Rio Grande region tu New Mexico. 
7. A. Schottii Torr. A glabrous shrub, with straight stipular spines: leaves fas- 
cicled ; pinna 1 pair ; leaflets 3 to 5 pairs, filiform-linear and thick, alternate, 4 mm. 
long: pod linear, curved into a semicircle or even a nearly complete circle, con- 
stricted between the seeds, short-stipitate, with coriaceous valves, 5 to 7.5 cm. long, 
6 mm. broad.—Cafion of the San Carlos crossing of the Rio Grande. Discovered by 
the Mexican Boundary Survey, and rediscovered recently at the same station by Dr. 
Havard. 
8. A. Reemeriana Schlecht. A stout smooth shrub with stout more or less curved 
prickles: pinne 2 or 3 pairs; leaflets 2 to 6 pairs, obliquely oblong or obovate, 
obtuse or retuse, very veiny, 8 to 10 mm. long: pod linear-oblong or oblong, obtuse, 
nore or less falcate, continuous within, flat, 6.5 to 10 em. long, 2.5 em. or less broad, 
on a short stipe, the valves somewhat coriaceous and transversely veiny.—Through- 
out Texas south of the Colorado and west to El Paso. 
9, A. malacophylla Benth. A softly pubescent (somewhat climbing?) shrub, with 
sparse somewhat recurved prickles: leaflets 2 or 3 pairs, oblique, obovate or oblong, 
obtuse, softly pubescent both sides, 6 to 12 mm. long, obscurely veiny: pod broadly 
linear, faleate, acute at base and shortly stipitate, subcoriaceous and with a slightly 
thickened margin, glabrous, 10 cm. long, 18 mm. broad.—‘‘ Uplands of the Leona 
River.” Var. GLABRATA Benth, is a glabrate form found near San Diego (Miss Croft). 
++ ++ Flowers in more or less elongated spikes. 
10. A. amentacea DC. A smooth shrub, with prominent stout straight stipular 
spines: pinne 1 pair; leaflets 2 pairs, obliquely oblong or obovate, obtuse or retuse, 
shining, with very prominent veins: pod narrowly linear, arcuate (often strongly 
so), constricted between the seeds, more or less pubescent, acute or acuminate, taper- 
ing below into a prominent stipe, 7.5 to 10 cm. long, 4 to 6 mm. wide,—From the 
Guadalupe to the lower Rio Grande and west to the Pecos. 
51. CALLIANDRA Benth. 
Ours are very low unarmed shrubs or even herbaceous, with bipinnate 
leaves, flowers in globose heads with elongated tubular corolla and 
long-exserted stamens, and straight or slightly curved pods with valves 
in dehiscing elastically revolute from apex to base. 
1. C. conferta Benth. A very low shrub, about 15 em. high, with pubescent 
branches and petioles: pinnz 1 pair; leaflets 8 to 12 pairs, crowded, scarcely 4 min. 
long, obliquely oblong, subcoriaceous, sericeous-villous beneath: pod sessile with a 
long-tapering base, appressed-villous, about 3.5 em. long and 6 mm. broad, the valves 
rather membranaceous on the sides and with thick margins. —High ground, from the 
headwaters of the San Felipe to the Rio Grande at Eagle Pass and westward into the 
mountains west of the Pecos. . 
2, C. eriophylla Benth. A low stout much branched shrub 7.5 to 30 cm. or more 
high, with pubescent branches and petioles: pinne 1 to 4 pairs: leaflets 6 to 12 pairs, 
minnte (1 to 5 mm, long or less), ovate or oblong, glabrous above, pilose beneath, 
soon glabrate and reticulate : pod linear-lancevlate, tapering from the middle to the 
base, acuminate, strigosely silky-canescent, with strongly thickened almost naked 
margins, 510 10cm, long, 6mm, broad (C. Chamedrys Engelm,).—From head of Leona 
River and Eagle Pass on the Rio Grande to the mountains west of the Pecos and of 
New Mexico. 
3. C. humilis Benth. Stems herbaceous nearly to the base, 15 to 25 cm. high, 
copiously pubescent to almost glabrate, from a very long horizontal lignescent root: 
pinn 3 to 6 pairs; leaflets 20 to 30 pairs, obliquely oblong, ciliate, glabrous above, 
