580 MIMOSACEAE 
linear-lanceolate to linear-oblong, 2-5 mm. long, acute, not reticulated : peduncles 1.5-2 
em. long, shorter than the subtending leaves: spikes smaller than those of A. Illinoensis: 
pods few, linear, 5-8 cm. long, straight or nearly so, acuminate at the apex. 
On prairies, Kansas to Texas. Summer. 
3. Acuan Jamésii (T. & G.) Kuntze. Stems branched at the base, the branches 
spreading, 1-5 dm. long, glabrous or nearly so: leaves with 4-12, usually 8-10 pinnae; 
leaflets 16-28, the blades oblong, 3-5 mm. long, not reticulated, more or less strongly apic- 
ulate: peduncles 1-2 em. long, much shorter than the subtending bracts: spikes about 1 
em. in diameter: pods linear, 3.5-8 cm. long, slightly curved, acuminate at the apex. 
In dry soil, the Indian Territory to Texas and Arizona. Spring and summer. 
4. Acuan velutina (Scheele) Kuntze. Stems branched at the base, the branches 
ascending or prostrate, 2-6 dm. long, finely canescent: leaves with 4-12 or usually 8-10 
pinnae ; leaflets numerous, the blades oblong, 2-5 mm. long, obtuse or acutish, not reticu- 
lated: peduncles 2.5-6.5 cm. long, shorter than the subtending leaves or longer: spikes 
about 1.5 cm. in diameter: pods linear, 2-6 cm. long, straight or nearly so, acuminate at 
both ends. 
In dry soil, southern and western Texas. Spring and summer. 
5. Acuan depréssa (Willd.) Kuntze. Stems branched at the base, the branches 
prostrate, 3-8 dm. long, glabrous or nearly so: leaves with 2-8 pinnae ; leaflets numerous, 
the blades narrowly oblong, 2-5 mm. long, obtuse or acutish, not reticulated : peduncles 
as long as the subtending bracts or shorter : pods linear, 4-6 mm. long, acuminate, straight. 
In sandy soil, near the coast, Florida to Texas and Mexico. Spring and summer. 
6. Acuan acuminàta (Benth.) Kuntze. Stems branched at the base, the branches 
spreading or prostrate, sparingly pubescent: leaves with 4-8 pinnae; leaflets 14-20, the 
blades oblong, 2-4 mm. long, acute, not reticulated, ciliate: peduncles 1-1.5 cm. long, 
shorter than the subtending bracts: pods linear, 3-4 cm. long, slightly curved, acuminate. 
In dry soil, southern Texas. Spring and summer. 
7. Acuan reticulata (Benth.) Kuntze. Stems branched at the base, the branches 
ascending or prostrate, 2-8 dm. long, sparingly pubescent : leaves with 4-8, usually 6 pin- 
nae: leaflets 8-20, the blades oblong to obovate, 3-5 mm. long, very oblique at the base, 
prominently reticulated, acute or acutish : peduncles elongated, 7-10 cm. long, surpassing 
the subtending bracts: spikes few-flowered, 1.5-2 cm. in diameter: pods linear, straight, 
4-6 cm. long, acuminate. 
In dry soil, southern Texas. Spring and summer. 
8. Acuan fallax Small. Stems branched at the base, the branches spreading or 
prostrate, 1-2 dm. long, finely canescent, angled. Leaves with 4-8 pinnae: leaflets mostly 
20-28, the blades oblong, slightly inequilateral, 3-5 mm. long, rather obscurely reticulated, 
acutish : peduncles elongated, 3-7 cm. long, surpassing the subtending bracts : spikes 
about 1 cm. in diameter: pods linear, 3-4 cm. long, slightly curved, acute. 
In dry soil, San Diego, Texas. Spring and summer. 
10. MORONGIA Britton.! 
Perennial herbs, or shrubby plants, mostly with spreading or prostrate prickle 
stems. Leaves usually sensitive: blades 2-pinnate : leaflets numerous, relatively small : 
stipels setaceous. Flowers perfect or polygamous, in axillary head-like spikes. Calyx 
4—5-lobed. Corolla of 4-5 petals united to about the middle. Stamens 8-10, exserted : 
filaments distinct or nearly so. Ovary nearly sessile. Ovules numerous. Pods narrow, 
prickly all over, 4-angled, or with broad margins, finally 4-valved by the valves separating 
from the margins. [Schrankia Willd., not Medic. ] 
-armed 
Leaflets prominently nerved beneath. 1. M. uncinata. 
Leaflets scarcely, if at all, nerved. ata 
Sides and margins of the pods with similar or nearly similar prickles. 2. M. angustata. 
Sides and margins of the pods with conspicuously dissimilar prickles. 5 
Pods scarcely flattened, the sides with long and broad prickles, the margins 
m ei unarmed; ear ners mm. ong ith 
s markedly flattened, the sides with very fine prickles, the margins wi cant, 
stouter prickles; beak 4-5 mm. long. d a 4. M. EE 
1. Morongia uncinata (Willd.) Britton. Stems armed with recurved prickles, di : 
dm. long: leaves with 6-12 pinnae; leaflets many, the blades oblong, 3-7 mm. : 
: c : t 
1A Mexican species, Morongia aculeata, has been reported from Texas, but I pan 
yet been able to examine authentic or satisfactory specimens. Species additional to 
here recognized have been described by Michaux and Chapman. 
3. M. latidens. 
