280 



PAPILIONACEAE. 



[Vol.. II. 



i. Lotus corniculatus L,. Bird' s-foot Trefoil. 

 Ground Honeysuckle. Bloom-fell. (Fig. 2084.) 



Lotus corniculatus L. Sp. PI. 775. 1753. 



Perennial from a long root, appressed-pubescent or 

 glabrate. Stems slender, decumbent, or ascending, 

 3 / -2 long; leaves 3-foliolate, short-petioled; leaflets 

 obovate, oblanceolate or oblong, 3 // -8 // long, obtuse 

 or acute; stipules similar to the leaflets, and often as 

 large; peduncles elongated, sometimes 4 / -6 / long, um- 

 bellately 3-i2-flowered; calyx-lobes acute, as long as 

 the tube, or shorter; corolla bright yellow, 6 // -9 // 

 long, or the standard reddish; pods linear, about i' 

 long, spreading, several-seeded. 



In waste places and on ballast, New Brunswick, and 

 about the seaports of the Eastern and Middle States. Ad- 

 ventive from Europe. Native also of Asia, and widely 

 distributed as a weed. Crowtoes (Milton), Cat's-clover, 

 Sheepfoot. June-Sept. 



2. Lotus Americanus (Nutt.) Bisch. Prairie Bird' s-foot Trefoil. (Fig. 2085.) 



Trigonella Americana Nutt. Gen. a: 120. 1818. 

 Lotus sericeus Pursh, Fl. Am. Sept. 489. 1814. Not DC. 1813. 

 ffosackia Purshiana Benth. Bot. Reg. under pi. 1257. 1829. 

 Lotus Americanus Bisch. Litt. Ber. Linnaea, 14: 132. 1840. 



Annual, erect, branched, villous-pubescent, or glabrate, 

 IO / -2O / high. Leaves 3-foliolate, or the upper sometimes 

 i-foliolate, sessile or the lower on petioles about i" long; 

 stipules minute or none; middle leaflet slightly lodger- 

 stalked than the lateral ones, oblong, the lateral lanceo- 

 late and more or less inequilateral, rounded at the base, 

 5 / '-8 // long, 2 // -3 // wide; peduncles axillary, i-flowered, 

 9 // -i2 // long in fruit, leafy-bracted at the summit; flowers 

 rose-color, about 2" long, the standard darker-veined; 

 keel acute; calyx-lobes linear, about twice the length of 

 the tube; pods linear, straight, about i' long, acute, 

 glabrous, 4-7-seeded, deflexed at maturity. 



In dry soil, Minnesota to Missouri, Arkansas, New Mexico 

 and Sonora. Summer. 



14. PSORALEA L. Sp. PI. 762. 1753. 



Herbs or shrubs, with dark glands or pellucid dots, i-5-foliolate leaves, and purple blue 

 pink or white flowers, mainly in spikes or racemes. Stipules broad. Calyx-lobes equal or 

 the lower longest, or the two upper ones sometimes united. Standard ovate or orbicular, 

 clawed; wings oblong or falcate; keel incurved, obtuse. Stamens monadelphous or diadel- 

 phous; anthers uniform. Ovary sessile or short-stalked, i-ovuled. Pod ovoid, short, inde- 

 hiscent, i-seeded. [Greek, scurfy, from the glandular dots, whence the name Scurfy-pea.] 



About i ip species, of wide geographic distribution. In addition to the following, about 20 

 others occur in the western United States. 



leaves digitately 3-s-foliolate (leaflets all from the same point). 

 Plants leafy-stemmed. 



Flowers small, 2" -4" long. 

 Pods subglobose. 



Leaflets narrowly oblong. 



Leaflets, except those of basal leaves, filiform-linear. 

 Pods ovoid, or ovate. 



Pods with a short, mostly abrupt beak. 



Flowers few, scattered in slender elongated racemes. 3. P. lenuiftora. 



Flowers numerous, clustered, or crowded in racemes. 



Leaflets oblong-obovate. 4- P- obtusiloba. 



Leaflets oblong. 5- P. floribunda. 



Pods with a slender sharp or elongated beak. 



Leaflets linear; flowers in loose elongated racemes. 6. P. lineari/olia. 



Leaflets linear-lanceolate, oblong, oblanceolate or obovate; flowers spiked. 

 Leaflets oblanceolate or obovate ; pubescence gray. 7. P. collina. 



Leaflets linear-lanceolate or oblong; pubescence silvery. 



Leaflets linear-lanceolate; calyx inflated in fruit. 8. P. digitata. 

 Leaflets oblong; calyx not inflated in fruit. 9. P. argophylla. 



Flowers large, 6"-8" long, densely spicate. 10. P. cuspidata. 



1. P. lanceolata. 



2. P. micrantha. 



