140 LEGUMINACEAE (BEAN FAMILY) 



dd. Plant annual. 



e. Leaflets obovate or obcordate, 0.6-1.2 cm. long; heads 1-1.4 cm. wide. 

 W. C. E. T. variegatum 



ee. Leaflets linear or oblong or lanceolate. 



f. Leaflets 1.6-2 cm. long, obtuse or emarginate; heads s-7-flowered, 1-1.5 



cm. wide; calyx lobes never 3-toothed. W. T. oliganthum 



ff. Leaflets 2.5-5 cm. long, obtuse or acute; heads more than 7-flowered, 2-3 



cm. wide; calyx lobes sometimes 3-toothed. W. T. tridentatum 



LOTUS (BIRD-FOOT TREFOIL) 



Annual or perennial. Leaves 3-i5-foliolate, ternate or pinnate; leaflets 

 entire. Flowers i to several in a leaf axil. Calyx 5-toothed or -cleft ; 

 teeth nearly equal. Petals free from the stamens, nearly equal. Stamens 

 diadelphous, in groups of 9 and i. Pods linear, flattish or terete, with spongy 

 partition between the seeds. Seeds i to several. (A Greek name for some 

 plants of this family.) 



A. Annual; flowers solitary (sometimes 2 on a peduncle in L. parviflora). 

 B. Flowers and pods nearly sessile. 



C. Stem glabrous, 3-6 dm. high, erect, sparingly branched; corolla pale yellow to 

 dark red. W. E. L. denticulatus 



CC. Stem pilose or villous, 1-1.5 dm. high, diffusely branched from the base; corolla 

 bright yellow. U. L. wrangelianus 



BB. Flowers and pods with peduncles nearly as long as the leaves, or longer. 



D. Leaflets lanceolate to ovate, usually villous; flowers 5-6 mm. long; bract at 

 top of peduncle i-3-foliolate. W. E. L. americanus (SPANISH CLOVER) 



DD. Leaflets oblong to ovate, usually glabrous; flowers 3-4 mm. long; bract at 

 top of peduncle i-3-foliolate. E. L. parviflorus 



AA. Perennial; flowers in umbels. 



E. Leaflets 3-9; flowers various, but with some yellow in them. 

 F. Leaves pubescent; flowers 4-13 mm. long. 



G. Stem procumbent or ascending, villous or tomentose; leaflets mostly acute, 



6-12 mm. long; pod i-2-seeded, its beak not hooked. W. E. L. decumbens 



GG. Stems erect or ascending, finely pubescent; leaflets mostly obtuse, 13-25 



mm. long; pod 5 or more seeded, its beak hooked. U. L. torreyi 



FF. Leaves glabrous or nearly so; flowers 14-20 mm. long. 



H. Flowers pure yellow. E. L. macbridei 



HH. Flowers with yellow standard but white or purple wings. 



I. Peduncles usually without a bract; corolla with yellow standard and white 



wings. W. E. L. bicolor 



n. Peduncles with a bract at the umbel ; corolla with yellow standard and purple 



wings. W. L. gracilis 



EE. Leaflets 9-15; flowers purple. W. E. L. crassifolius 



PSORALEA (PSORALEA) 



Perennial. Leaves 3~7-foliolate, punctate with dark glands or pellucid 

 dots ; stipules wide. Flowers blue or pink or white. Stamens monadel- 

 phous or diadelphous. Pod ovoid, short, indehiscent. Seed i. (Gk. 

 psoraleos = scurfy ; referring to the glands or dots on the leaves.) 



A. Leaflets broadly ovate; seed grayish. W. E. P. physodes 



AA. Leaflets lanceolate; seed light brown. E. P. lanceolata 



