Voi,. II.] 



MIMOSA FAMILY. 



255 



2. ACUAN Med. Theod. Sp. 62. 1786. 



[DESMANTHUS Willd. Sp. Pi. 4: 1044. 1806.] 

 [DARUNGTONIA DC. Ann. Sci. Nat. 4: 97. 1825.] 



Perennial herbs or shrubs, with bipinnate leaves, small stipules, and greenish or whitish 

 small regular flowers in axillary peduncled heads or spikes. Flowers perfect, sessile, or the 

 lowest sometimes staminate, neutral or apetalous. Calyx campanulate, its teeth short. 

 Petals valvate, distinct, or slightly united or coherent below. Stamens 10 or 5, distinct, 

 mainly exserted; anthers all alike. Ovary nearly sessile; ovules co . Pod linear, straight or 

 curved, acute, glabrous, flat, several-seeded, 2-valved, the valves coriaceous or membranous. 

 About 10 species, natives of warm and tropical America, one of them widely distributed in 

 tropical regions of the Old World. 

 Pods few, linear, erect, straight. i. A. leptoloba. 

 Pods numerous in globose heads, oblong, curved. 



2. A. Illinoensis. 



i. Acuan leptoloba (T. & G.) Kuntze. 

 Prairie Mimosa. (Fig. 2029.) 



Desmanthus leptolobus T. & G. Fl. N. A. i: 402. 1840. 

 Acuan leptoloba Kuntze, Rev. Gen. PI. 158. 1891. 



Herbaceous, ascending, branched, stems rough- 

 angled, 2-3 long. Leaves short-petioled, bipin- 

 nate; pinnae 5-10 pairs, sessile; leaflets 10-24 

 pairs, sessile, linear-lanceolate, acute, inequilateral, 

 rounded at the base, usually glabrous, i^ // -2 // 

 long, y 2 " wide or less; peduncles 6 // -i2 // long, few- 

 flowered; stamens (always?) 5; pods 3-8, narrowly 

 linear, acuminate, nearly straight, glabrous, about 

 3 times the length of the peduncle, 6-8-seeded. 



Prairies, Kansas to Texas. Summer. 



2. Acuan Illinoensis (Michx.) 

 Kuntze. Illinois Mimosa. (Fig. 2030.) 



Mimosa Illinoensis Michx. Fl. Bor. Am. 2: 254. 



1803. 



Acacia brachyloba Willd. Sp. PI. 4: 1071. 1806. 

 Desmanthus brachylobus Benth. in Hook. 



Journ. Bot. 4: 358. 1842. 

 Acuan Illinoensis Kuntze, Rev. Gen. PI. 158. 



1891. 



Ascending or erect, glabrous or nearly so, 

 stems angled, i-3 high. Foliage resem- 

 bling that of the preceding species, but the 

 pinnae and obtusish leaflets are sometimes 

 more numerous; peduncles i / -3 / long; pods 

 numerous, densely capitate, oblong or lanceo- 

 late, strongly curved, 8 // -i2 // long, acute, 

 slightly impressed between the 2-5 seeds. 



Prairies and river-banks, Indiana to Kentucky, 

 Florida, Minnesota and Texas. May-Sept. 



3. MORONGIA Britton, Mem. Torr. Club, 5: 191. 1894. 

 [SCHRANKIA Willd. Sp. PI. 4: 1041. 1806. Not Medic. 1792.] 



[LEPTOGLOTTIS DC. Mem. Leg. 451. 1823?] 



Perennial herbs, or shrubs, mainly prostrate or procumbent, armed with recurved 

 prickles. Leaves bipinnate, usually sensitive; leaflets numerous, small; stipules setaceous. 

 Flowers regular, small, 4~5-parted, pink or purple, perfect or polygamous, in axillary pe- 

 duncled heads or spikes. Petals united to the middle. Stamens usually 8-12, distinct or 

 united at the base; anthers all alike. Ovary nearly sessile; ovules co . Pod linear, acute or 

 acuminate, spiny all over, at length 4-valved, several seeded. [Named in honor of the late 

 Rev. Thos. Morong, a contributor to this work. ] 



About 10 species, natives of warm and tropical America, I in tropical Africa. 



Leaflets elliptic, strongly veined. i. M. uncinala. 



Leaflets linear-oblong, scarcely veined. 2. M. angustata. 



