Mimosa acantholoba (Willd.) Poir.

Neomimosa russellii Britton & Rose, sp. nov
A shrub, armed with numerous short, reflexed prickles, the twigs angled, puberulent. Petiole and rachis prickly; pinnae 8-10 pairs; leaflets 10-15 pairs, oblong-linear, oblique at base, 5-6 mm. long; legume elliptic, 6-8 cm. long, 2 cm. broad near the middle, ovate at tip, long-apiculate, cuneate at base, stipitate, the margin sparingly prickly, the valves unarmed; seeds usually 3.
Rosario, Sinaloa, August 4, 1910, Rose, Slandley & Russell 14555.

Neomimosa colimensis (B. L. Robinson) Britton & Rose
Mimosa colimensis B. L. Robinson, Proc. Bost. Soc. Nat. Hist. 31: 258. 1904.
Branches glabrous, somewhat angled, prickly, the prickles small. Leaves large, up to 2 dm. long; pinnae 15-18 pairs; rachis prickly or unarmed; leaflets 27-32 pairs, linear-oblong, 4 mm. long, acute, puberulent beneath; inflorescence elongated, paniculate; peduncles 1-1.8 cm. long, slender, puberulent; flowers in dense oval-globose heads; caly.x and corolla glabrous; stamens 10, slender.
Type locality; Colima. Distribution: Colima.

Neomimosa eurycarpoides (B. L. Robinson) Britton & Rose
Mimosa eurycarpoides B. L. Robinson. Proc. Am, Acad. 36; 472. 1901.
A shrub, the twigs glabrous, somewhat angled, sparingly if at all prickly. Leaves large, up to 2 dm. long; pinnae 6-12 pairs; leaflets 20-30 pairs, linear, 3-8 mm. long, about 1.5 mm. wide, acutish, appressed-pubescent; peduncles often in two's or three's, 1.5 cm. long, or shorter, axillary or in terminal panicles; calyx and corolla glabrous; stamens 8 or 10; legume oblong, stipitate, 8-12 cm. long, 1.5-2 cm. wide, the valves sparingly setose, the margins with a few prickles, or unarmed, the base cuneate.
Type locality: Near Colomas, Sinaloa. Distribution: Sinaloa. to Guerrero.