622 FABACEAE 



small, semisagittate, lanceolate-subulate; peduncles slender, about half as long as the leaves, 

 2-3-flowered; flowers purple, 10 mm. long; calyx-teeth deltoid, scarcely 2 mm. long; pods 3-4 

 cm. long. 



Stony hillsides, Arid Transition Zone; Whitman County, Washington, and adjacent Idaho. Type locality: 

 Latah County, Idaho. May-July. 



Lathyrus bijugatus var. Sandbergii White, loc. cit. This is merely a form of the species with linear or 

 linear-lanceolate leaflets. It grows in similar situations and has about the same range. 



8. Lathyrus rigidus White. Rigid Pea. Fig. 2943. 



Lathyrus albus S. Wats. Bot. Calif. 2: 442. 1880. Not Kittel. 

 Lathyrus rigidus White, Bull. Torrey Club 21: 45S. 1894. 



Perennial, glabrous and somewhat glaucous, the stems stout, several to many from a woody 

 rootstock, erect or the base decumbent, 1.5-3 dm. high. Leaflets 6-10, oblong-lanceolate to ob- 

 lanceolate, cuspidate, 1-2 cm. long, rigid and strongly veined; tendrils none or rudimentary; 

 stipules semisagittate, as large as the leaflets; peduncles usually a little longer than the leaves, 

 1-3-flowered; flowers white, 15-20 mm. long; calyx-teeth narrowly-lanceolate to deltoid, shorter 

 than the tube ; pod glabrous, 30-35 mm. long ; seeds usually 3. 



Dry hillsides, Arid Transition Zone; Blue Mountains, eastern Oregon, south to Modoc County, California. 

 Type locality: Union County, Oregon. April-June. 



9. Lathyrus nevadensis S. Wats. Sierra Nevada Pea. Fig. 2944. 



Lathyrus venosus var. obovatus Torr. Pacif. R. Rep. 4: 77. 1857. 

 Lathyrus nevadensis S. Wats. Proc. Amer. Acad. 11: 133. 1876. 

 Vicia nana Kell. Proc. Calif. Acad. 7: 89. 1876. 

 Lathyrus obovatus White, Bull. Torrey Club 21 : 455. 1894. 



Perennial, glabrous or sparingly pubescent, the stems erect, slender or rather stout, often 

 branched, 1-5 dm. high. Leaflets 4-8, ovate to ovate-oblong, or especially those of the lower 

 leaves often obovate, 1-3 cm. long, rather thin ; stipules small, semisagittate, lanceolate-subulate ; 

 tendril a short bristle; peduncles usually a little exceeding the leaves, 2-4-flowered; calyx gla- 

 brous or sparingly pubescent, the longer lower teeth shorter than the tube ; corolla about 20 mm. 

 long, bluish purple, or the wings and keel somewhat ochroleucous ; pods glabrous. 



Open coniferous forests, Arid Transition Zone; Wallowa and Blue Mountains, Oregon, south to the central 

 Sierra Nevada, California. Type locality: Sierra Nevada, Calaveras County, California. March-June. 



Lathyrus nevadensis subsp. stipulaceus (White) Bradshaw, Bot. Gaz. 80: 244. 1925. (L. obovatus var. 

 stipulaceus White, Bull. Torrey Club 21: 455. 1894.) Stipules larger, broadly lanceolate, the lower segment 

 often toothed, tendrils often 15-20 mm. long; peduncles usually with more flowers. Eastern Washington and 

 adjacent Idaho. Type locality: between Colville and Spokane, Washington. 



10. Lathyrus Nuttallii S. Wats. Nuttall's Pea. Fig. 2945. 



Lathyrus pubescens Nutt. ex Torr. & Gray, Fl. N. Amer. 1 : 274, as a synonym. 1838. Not Hook. & Arn. 

 Lathyrus Nuttallii S. Wats. Proc. Amer. Acad. 21: 450. 1886. 

 Lathyrus lanceolatus Howell, Fl. N.W. Amer. 1: 158. 1898. 



Perennial, sparingly pubescent, the stems slender, 4-9 dm. high, ascending or erect, branch- 

 ing. Leaflets 6-14, commonly 8, narrowly to broadly elliptic, acute, 2-5 cm. long ; stipules small, 

 semisagittate, lanceolate-subulate, entire; tendrils well-developed, slender, simple or divided; 

 peduncles about as long as the leaves, 5-7-flowered; calyx pubescent, the longer lower teeth 

 lanceolate, shorter than the tube; corolla 15 mm. long, the standard bluish purple, the other petals 

 whitish ; pods pubescent, narrow, about 3 . 5 cm. long. 



In open woods, Humid Transition Zone; Vancouver Island and western Washington south to northern Cali- 

 fornia and Klamath County, Oregon. Type locality: probably along the lower Columbia River. May-July. 



11. Lathyrus Lanszwertii Kell. Nevada Pea. Fig. 2946. 



Lathyrus Lanszwertii Kell. Proc. Calif. Acad. 2: 150. fig. 44. 1863. 

 Lathyrus coriaceus White, Bull. Torrey Club 21: 452. 1894. 

 Lathyrus oregonensis White, Bull. Torrey Club 21 : 456. 1894. 

 Lathyrus Goldsteiniae Eastw. Bull. Torrey Club 32: 197. 1905. 



Perennial, sparingly puberulent throughout, the stems rather stout and somewhat climbing, 

 2-6 dm. high, little or not at all branched. Leaflets 6-12, linear-lanceolate to linear-elliptic, acute 

 or obtuse, firm and coriaceous, strongly veined, 3-5 cm. long; stipules semisagittate, 10-15 mm. 

 long, narrowly lanceolate ; tendrils well-developed, forked ; peduncles much shorter than the 

 leaves, 4-10-flowered; calyx-teeth unequal., the lower triangular-lanceolate, shorter than the tube; 

 corolla 15 mm. long, the standard bluish purple, the wings often purple-tinged; pod slender, 

 3 cm. long, glabrous. 



Moist ground and thickets, Arid Transition Zone; eastern Washington to western Nevada and the eastern 

 slopes of the Sierra Nevada, California. Type locality: Wasco, Nevada. May-July. 



Lathyrus Lanszwertii subsp. aridus (Piper) Bradshaw, Bot. Gaz. 80: 247. 1925. (L. coriaceus subsp. 

 aridus Piper, Proc. Biol. Soc. Wash. 31: 190. 1918.) Leaflets 6 or 8, very rarely only 4, narrowly linear-lanceo- 

 late, 4-7 cm. long; tendrils usually simple; corolla about 10 mm. long. Open forest, Arid Transition Zone; Klicki- 

 tat County, eastern Washington, to the central Sierra Nevada, California. Sierran forms of this have erroneously 

 been referred to Lathyrus graminifolius S. Wats. 



12. Lathyrus palustris L. Marsh Pea or Vetchling. Fig. 2947. 



Lathyrus palustris L. Sp. PI. 733. 1753. 



Perennial, glabrous or sparsely pubescent; stems angled and usually winged, slender, 3-8 



