LEGUMINOSAE (PULSE FAMILY) 523 



Calyx 4-5 mm. long, much shorter than the pod. 



Leaflets densely velvety beneath 4. Z. Briitonii. 



Leaflets appieshed-pubescent or sparingly villous beneath . 5. L. Xuttallii. 

 Calyx 6-9 uun. long, about equaling the pod . . . . 6. Z. Manniana. 



ct. Few if any of the peduncles exceeding the leaves e. 



e. Calyx of the petaliferous flowers 3—5 mm. long, rarely half as 

 long as the pod. 

 Leaflets densely woolly or velvety beneath .... 7. L. Stuvei, 



Leaflet? glabrate or appressed-pubescent beneath. 

 Leaflets linear to linear-oblong ; petaliferous inflorescences 



mostly sessile or subsessile 8. Z. mrginicct 



Leaflets oval to oblong ; petaliferous inflorescences often 



short-peduncled 9. L. frutescem. 



e. Calyx of the petaliferous flowers 6-8 mm. long, two thirds as 



long as the pod 10. Z. siiuulata. 



t. Flowers all alike and perfect, in close spikes or heads ; corolla whitish 



or cream-color, with a purple spot on the standard, about the 



length of the calyx /. 



/. Peduncles mostly shorter than the dense subglobose heads ; flowers 



closely appressed-ascending. 



Stem pubescent with long spreading or loosely ascending hairs, 



rarely glabrate ; calyx 8-12 mm. long 12. L.capitata. 



Stem short-pubescent with chiefly appressed hairs or glabrate ; 



calyx 5-7 mm. long . .' 13. L. angusti/olia. 



f. Peduncles elongate, chiefly equaling the cylindric or subcylindric 

 spikes. 

 Spikes thick-cylindric, 1-1.5 cm. thick. 

 Stems with" long spreading or loosely ascending pubescence ; 

 leaflets oblong to orbicular ; flowers spreading or loosely 



ascending 11. Z. hirta. 



Stems chiefly appressed-pubescent or glabrate; leaflets linear to 



linear-oblong; flowers appressed-ascending . , . .13. L. anguf,tifolia. 

 Spikes slender-cylindric, 5-S mm. thick . , , . . . 14. Z. leptostachya. 

 a. Stipules and bracts broad and scarious ; calyx-lobes broad ; annual . 15. L. striata. 



1. L. prociimbens Michx. Stem trailing., prostrate or nearly so, soft-downy 

 with short spreading haii-s ; leaflets do\Miy, oval or obovate-elliptical, 6-18 mm. 

 long ; peduncles very slender, few-flowered ; keel equaling the wings ; pod small, 

 roundish. — Dry sandy soil, chiefly near the coast, s. N. H. to 11a. and Tex. ; 

 inland in Miss, basin to Mo,, 111., and Ind. Fl, late Aug,, Sept, 



2. L. repens (L.) Bart. Like the preceding but more slender and glabrous 

 or finely appressed-puhescent; stipules subrigid, mostly 2-4.5 mm, long. — 

 Sandy or rocky soil, chiefly near the coast, Ct. to Fla. and Tex., inland in 

 Miss, basin to Ky., Ind., and Minn. ; common and said to flower earlier than 

 the preceding. 



3. L. vioiacea (L,) Pers. Stems upright or spreading, slender, branched, 

 2-7 dm. high, rather sparsely leafy and sparingly lubescent ; stipules setaceous, 

 mostly 5-8 mm. long; leaflets thin, broadly oval or oblong, finely appressed- 

 pubescent beneath, those of the stem-leaves mostly 2-5 cm. long, 1,2-2.2 cm. 

 broad ; peduncles very slender, loosely feiofloicered, mostly longer than the 

 leaves ; petals 6-8 mm. long, the keel often the longest ; pod ovate. 4-0 mm, 

 long, minutely strigose, — Dry copses, s. N. H, and Vt. to Minn., e, Kan., La., 

 and Fla., chiefly at low altitudes, July-Sept. Var. prairea Mackenzie & 

 Bush, Principal leaflets 1-2 cm. long, 0.5-1 cm. broad. (Z. prairea Britton,) 

 — Dry prairies, Mo. and Kan,, southw. 



4. L. Brittbnii Bicknell. Densely cinereous-velvety or -tomentose ; stems 

 loosely ascending or arching, 6-18 dm. long ; leaves mostly short-petioled, the 

 thick oblong or lance-elliptic leaflets velvety beneath, cinereous-pilose or glabrate 

 above, the principal ones 1,5-4 cm, long; inflorescences numerous along the 

 upper half of the stem or on short lateral branches ; peduncles various, some 

 shorter than the leaves, others elongate ; calyx 4-5 mm. long ; corolla 6-8 mm. 

 long, pink and purple, the standard deeper purple at base ; pod tomentose, 

 sharply acute or acuminate. — Dry soil, near the coast, e. Mass. to Md. ; local 

 and little known. 



5. L. Nuttallii Darl. Stems erect, stoutish, 6-12 dm. high, villous; leaves 

 mostly long(l-3 cm.)-petioled, the oval leaflets glabrous or glabrate above, 

 appresspd-pubescent or sparingly villous beneath, the principal ones 2.5-4 cm. 

 long ; peduncles of various lengths ; calyx 4-6 mm. long, much .shorter than the 



