58 DIALYPETALOUS EXOGENS 



rhombic-ovate ; racemes pendulous ; radical peduncles filiform, bear- 

 ing apetalous and often merely pistillate flowers. 

 MONOICOUS AMPHICARPAEA. Hog Pea-nut. 



Annual ? Stem 3 to 6 or 8 feet long, sparingly branched. Lea.flds 1 to 2 or 3 

 inches long ; common petioles 1 to 3 or 4 inches long. Racemes axillary, on pedun- 

 cles half an inch to near 3 inches in length; flowers pale purple, or nearly white ; 

 peduncles from near the base of the stem 2 to 8 or 10 inches long, often branching, 

 mostly with a solitary legume at the extremity, which is buried in loose earth, or 

 under old leaves, near the root. Cauline legumes about an inch long, subfalcate, 

 3- or 4-seeded; seeds subreniform, dark purple : Hypogaean legumes about one-third 

 of an inch long, compressed, suborbicular, hirsute, tawny, 1-seeded ; seed com- 

 presed, orbicular, mottled reddish-brown. 

 Hah. Woods, and thickets : frequent. Fl. Aug. Fr. Sept. 



TRIBE 3. HEDYSA^REAE. 



Leaves mostly trifoliolate, the leaflets often stipellate ; stamens sometimes mona- 

 delphous ; legume (or lament) separating transversely into 2 or more 1-seeded inde- 

 hiscent joints, or sometimes reduced to 1 such joint ; cotyledons thin, becoming 

 green in germination. 



95. DESMO v mtIM ? DC. 



[Gr. Desmos, a chain, and eidos, form; alluding to the jointed pods.] 

 Calyx somewhat bilabiate. Legume compressed, deeply lobed on 

 the lower margin, finally separating into 2 or more tenaciously 

 hispid joints. Perennial herbs, with pinnately trifoliolate leaves; 

 leaflets stipellate ; flowers more or less purplish, in terminal or axil- 

 lary racemes, which are often elongated and paniculate. 



gl. STEM erect, or ascending : racemes mostly elongated, terminal and subterminal. 

 f Stipules inconspicuous, setaceous, or subulate; legumes of 2 to 4 joints. 



1. 1>. nudifluriim, DC. Leaves all crowded at the summit of 

 the sterile stem ; panicle on a tall and mostly naked scape. 

 NAKED-FLOWERED DESMODIUM. 



Stem 6 to 12 inches high. Leaflets 2 to 3 inches long, obliquely ovate, acute ; 

 common petioles 2 to 6 inches in length. Racemes paniculate, slender, on a scape- 

 like peduncle 18 inches to 3 feet long, which proceeds from near the root, and is 

 mostly decumbent at base, becoming nearly upright at a little distance, and ap- 

 pearing like a distinct plant, sometimes bearing 1 to 2 trifoliolate leaves. Joints of 

 the legume usually 3 or 4, somewhat triangular, slightly connected. 

 Hob. Woodlands : common. Fl. July. Fr. Sept. 



2, D. ac u mi II ill ii ill, DC. Leaves all crowded at the summit 

 of the stem, from which arises the long-peduncled panicle ; leaflets 

 orbicular-ovate, acuminate. 



ACUMINATE DESMODIUM. 



Stem 9 to 15 inches high. Leaflets 2 to 4 or 5 inches long, thin; common petioles 

 2 to 6 or 8 inches in length. Racemes paniculate, slender, on a terminal peduncle 

 12 to 18 inches long. Joints of the legume 2 or 3 (often 1), slightly connected, 

 broad, semi-obovate, pubescent and tenacious. 

 Hob. Rich woodlands : common. Fl. July. Fl. Aug. 



3. D. pane if lor um, DC. Leaves scattered along the low- 

 ascending stem ; leaflets rhombic-ovate ; raceme few-flowered, on a 

 short peduncle. 



