LEGUMINOSAE (PEA FAMILY) 30l 



1. Vicia americana Muhl. Willd. Sp. PI. 3: 1906. 1803. Glabrous; stems 

 climbing or scrambling, 5-10 dm. long: leaflets 10-14, elliptical-lanceolate or 

 ovate-oblong, obtuse or retuse, mucronate, 20-30 mm. long; stipules deeply 

 toothed: peduncles shorter than the leaves, 4-8-flowered; flowers purplish- 

 blue, 18-20 mm. long: pods linear-oblong, reticulated. — Frequent; across the 

 continent especially northward. 



la. Vicia americana oregana (Nutt.) A. Nels. Somewhat pubescent; stems 

 weak: leaves mostly lance-oblong, usually some of them truncate or serrate 

 at apex. {V. oregana Nutt. and V. truncata Nutt. T. & G. Fl. 270.) 



2. Vicia linearis (Nutt.) Greene, Fl. Francis. 3. 1891. Nearly glabrous; 

 stems decumbent or scrambUng: leaflets 8-14, Unear, often obtuse, apiculate; 

 tendrils short, simple or bifid; stipules laciniate-toothed or incised below: pe- 

 duncles 3-4iflowered, shorter than the leaves; flowers large (18-25 mm. long), 

 pale purple: style nearly filiform, villous around the summit. — Very common 

 throughout our range and westward. 



2a. Vicia linearis caespitosa A. Nels. A reduced form, the stems branched 

 and matted. — With the species. 



3. Vicia jjroducta Rydb. Bull. Torr. Club 28; 500. 1901. Sparsely pubes- 

 cent perennial; stems slender, branched, angled and leafy: leaflets 6-10, ob- 

 long to linear: peduncles 2-3-flowered, distinctly produced beyond the small 

 lateral flowers: calyx-tube about 2 mm. long, exceeding its lance-subulate 

 teeth: corolla ochroleucous with purpUsh tip.— Southern Colorado. 



18. LATHYRUS L. Pea or Vetch 



Our species are perennial and mostly smooth plants, the raohis of the 

 leaves in some not produced into a tendril. Style flattish, dilated (not grooved) 

 above, hairy along the inner side (next the free stamen). Sheath of the fila- 

 ments scarcely oblique at the apex. Otherwise nearly as in Vicda. 



Flowers purple. 



Leaves not tendril-bearing. 

 Leaves linear. 



Glabrous 1, L. omatus, 



Villous-canescent . . . • . • • • ,2. L. incanus. 

 Leaves lance-oblong . , . • , » , . ,3. L. deoaphyllus. 

 Leaves 'tendril-bearing , • , • • • • . .4. L. arizonicus. 

 Flowers white or yellowish. 

 Leaves linear to oblong. 

 Stipules semisagittate . , ••• ••• ,5. L. leucanthus. 



Stipules foliaceous 6.- L. ochroleucus. 



Leaves ovate, conspicuously veiny 7. L. utahensis. 



1. LathyrusornatusNutt.T.&G.Fl. N.A.I: 277. 1838. Erect, glabrous, 

 often glaucous; stem 1-2 dm. high, sometimes branched, quadrangular: leaf- 

 lets 3-4 pairs, lanceolate-linear, acute, mucronate, rigid and strongly veined, 

 tendrils scarcely any; stipules Unear-lanceolate and slender, semisagittate, 

 entire: peduncles about 4-flowered, longer than the leaves; flowers large, 

 purple, 2-3 cm. long, very showy: calyx-teeth subulate, slightly unequal, 

 rather shorter than the tube: pod smooth, flat, acuminate at each end. — Plains 

 at the eastern base of the Rocky Mountains. 



2. Lathyrus incanus Rydb. Size and habit of the preceding, densely 

 villous-oanescent throughout, otherwise quite similar.— Sandy ba'nks and 

 washes; Wyoming and Nebraska. i' 



3. Lathyrus decaphyllusPursh, Fl. Am. Sept. 471. 1814. Mostly glabrous; 

 stem erect, slightly woody at the base, much branched, a little quadrangular, 

 about 3 dm. high: leaflets 2-5 pairs, elliptical-lanceolate,, somewhat glaucous, 

 rigid, strongly veined; stipules lanceolate, subfalcate, semisagittate at base: 

 peduncles JP-S-flowered, rather shorter than the leaves; flowers large, purple: 

 -■jgments of the calyx broadly or narrowly subulate, somewhat unequal, 

 shorter than the tube: pod large, glabrous. L. polymorphus. — Throughout 

 the Rocky Mountains of the United States. 



4. Lathyrus arizonicus Brit. Trans. N. Y. Acad. Sci. 8: 65. 1889. Per- 

 ennial, glabrous or somewhat pubescent; stem; often winged: leaflets 4-8, 



