618 FABACEAE 



mm long sparsely strigose on both surfaces ; peduncles shorter than the leaves ; raceme densely 

 flowered, 'one-sided; flowers reddish purple, about 12 mm. long; pod oblong, 3-4 cm. long, 

 several-seeded; seeds globose, black. 



Borders of swamps and streams near the coast, Humid Transition and Canadian Zones; southern Alaska to 

 Monterey County, California, extending inland to the Willamette Valley, Oregon. Type locality: open woods on 

 the Columbia River. March-July. 



Vicia disperma DC. Cat. Hort. Monsp. 154. 1813. Annual, somewhat pilose with 8-10 pairs of linear- 

 oblong mucronate leaflets; peduncles 2-3-flowered, shorter than the leaves; flowers minute; calyx-lobes lanceo- 

 late-subulate, about equaling the corolla; pod oblong, 2-seeded. Native of southern Europe, locally introduced at 

 Berkeley, California. 



Vicia pannonica Crantz, Stirp. Aust. ed. 2. 393. , 1769. Hungarian Vetch. Annual, with reclining or 

 climbing stems, 2-6 dm. long. Leaves with very short petioles; stipules small; leaflets 8-16, linear to oblong, ong- 

 villous especially when young; peduncles very short, 2-4-flowered; flowers yellowish white, 15-18 mm. long. 

 Introduced from Europe and becoming established in several places in Willamette Valley, Oregon, and Sonoma 

 County, California. 



25. LATHYRUS L. Sp. PI. 729. 1753. 



Annual or mostly perennial, herbaceous vines or rarely erect herbs. Leaves pinnate, 

 the rachis usually produced into a tendril. Flowers in axillary racemes or sometimes 

 solitary. Calyx obliquely campanulate or gibbous at the base, its teeth nearly equal, or 

 the upper shorter. Corolla nearly as in Vicia but commonly larger, and proportionately 

 shorter for its breadth. Stamens diadelphous or monadelphous below. Style curved, flat- 

 tened, hairy along the inner side. Pod flat or sometimes terete, 2-valved. [Ancient Greek 

 name of some leguminous plant.] 



About 100 species, natives of the northern hemisphere and South America. Type species, Lathyrus syl- 

 vestris L. 



Leaflets none; the stipules large, simulating a pair of large opposite cordate leaves. 1. L. Apliaca. 



Leaflets present. 



Leaflets a single pair. 



Annual; flowers 1 or 2 on the peduncle, 8-10 mm. long. 2. L. pusillus. 



Perennial; stems strongly winged; flowers several on the peduncle, 2 mm. long. 3. L. latifolius. 

 Leaflets more than 1 pair. 



Tendrils reduced and bristle-like, sometimes wanting, or sometimes once forked in Nuttallii. 



Plants densely silky-villous. 4. L. littoralis. 



Plants not densely silky-villous. 



Flower solitary (rarely 2) on a short slender pedicel-like peduncle. 5. L. Torreyi. 



Flowers in 2- to several-flowered racemes. 



Leaflets linear-lanceolate, longer than the leaf-rachis. 



Flowers 15-20 mm. long, white. 6. L. Cusickii. 



Flowers 10 mm. long, purple. 7. L. bijugatus. 



Leaflets oblong-lanceolate to obovate, shorter than the rachis. 

 Flowers purple. 



Leaflets oblong-lanceolate, coriaceous, glabrous; tendrils rudimentary. 



8. L. rigidus. 



Leaflets ovate, thin, thinly pubescent; tendrils simple or sometimes forked. 



10. L. Nuttallii. 



Flowers white or yellowish. 9. L. nevadensis. 



Tendrils well developed and usually forked. 



Stems prominently winged on two of the angles. 



Stems slender; leaflets 2-3 pairs; peduncles 2-6-flowered. 12. L. palustris. 



Stems stout; leaflets 4-6 pairs; peduncles 6-15-flowered. 



Plants puberulent. 13- L. Watsonii. 



Plants glabrous. 14. L. Jepsonii. 



Stems merely angled, or the angles rarely narrowly margined. 

 Plants glabrous. 



Flowers cream-yellow, fading brownish yellow, 10-12 mm. long. 15. L. sulphureus. 

 Flowers more or less violet-purple. 



Stipules large, over half the size of the adjacent leaflets. 



Stipules as large as the leaflets. 16. L. maritimus. 



Stipules about half as large as the leaflets. 17. L. polyphyllus. 



Stipules narrow, thin, half the size of the adjacent leaflets. 



Flowers 20-25 mm. long. 18. L. pauciftorus. 



Flowers 12-15 mm. long. 19. L. Schaffneri. 



Plants more or less pubescent. 



Corolla 10-12 mm. long; leaflets linear or linear-lanceolate. 11. L. Lanszwertii. 



Corolla 15 mm. or more in length. 



Corolla 15-18 mm. long; lower calyx-lobes usually well exceeding the tube, lanceolate. 

 Leaves and calyx more or less densely tomentose-pubescent; racemes shorter than 



the leaves. 20. L. vestitus. 



Leaves and calyx glabrous or essentially so; racemes often longer than the leaves, 

 many-flowered. 21. L. Bolanderi. 



Corolla 20-35 mm. long; lower calyx-lobes narrowly subulate, shorter than or about 

 equaling the tube. 

 Standard not strongly reflexed. 



Flowers cream or flesh-colored, 20 mm. long. 22. L. laetiflorus. 



Flowers rose-colored, 20-25 mm. long. 23. L. Alefeldii. 



Standard strongly reflexed and lying back on the base of the flower; petals all 

 deep red. 24. L. splendens. 



