PA P2L ION A CEA E. $6? 



long; calyx-teeth unequal, shorter than the tube; pod 2-3 cm. long, glabrous. 

 Near Hamilton, Out. Adventive or fugitive from Europe. May-July. 



Ervum Lt'ns 1.., the Lentil, distinguished from all our species of Vicia by its elon- 

 gated calyx-lobes and oval, i-2-seeded pod, is collected occasionally as a waif. 



37. LATHYRUS L. 



Herbaceous vines, rarely erect herbs, with pinnate mostly tendril-bearing leaves, 

 and racemose or sometimes solitary flowers. Calyx oblique or gibbous at the base, its 

 teeth nearly equal or the upper ones somewhat shorter than the lower; corolla nearly 

 as in Vicia, but commonly larger; stamens diadelphous (9 and I), or monadelphous 

 below. Ovary sessile or stalked; ovules generally numerous; style curved, flattened, 

 hairy along its inner side; pod flat, or sometimes terete, 2-valved, dehiscent, con- 

 tinuous between the seeds. [Ancient Greek name of some leguminous plant. 

 About no species, natives of the northern hemisphere and of S. Am. Besides the 

 following, about 25 others occur in southern and western N. Am. 



Leaflets 3-7 pairs ; flowers purple. 



Stipules foliaceous ; plant of the seashore and the Great Lakes, i. L. maritimus. 

 Stipules half-sagittate or small, or wanting ; inland plants. . 



Plants climbing or trailing ; stipules present ; pod sessile. 



Leaflets ovate or oval, large ; flowers 10-20. 2. L. venosus. 

 Leaflets linear, oblong or oval, smaller ; flowers 2-6. 



Leaflets linear or linear-oblong ; stem winged. 3. L. pahistris. 



Leaflets oblong or oval ; stem wingless. 4. L.. myrtifolius. 

 Plants mainly erect ; stipules often wanting ; pod stipitate. 



Leaflets lanceolate or oblong. 5. L. decaphyllus. 



Leaflets linear.- 6. L. ornatus. 



Leaflets 3-5 pairs ; stipules foliaceous ; flowers yellowish-white. 7. L. ochroleucus. 

 Leaflets i pair ; stipules foliaceous. 



Perennial ; introduced ; flowers yellow. 8. L. pratensis. 



Annual ; native western species ; flowers purple. 9. L. pusillus. 



1. Lathyrus maritimus (L.) Bigel. BEACH PEA. (I. F. f. 2215.) Peren- 

 nial, glabrous or nearly so. slightly glaucous; stems angled, decumbent, 3-6 dm. 

 long. Stipules ovate, half- hastate, acute, 2.5-5 cm - l n g; leaves nearly sessile; 

 leaflets 3-6 pairs, oblong, oval or obovate, obtusish and mucronulate at the apex, 

 mainly narrowed at the base, somewhat larger than the stipules; tendrils branched ; 

 peduncles shorter than the leaves; flowers 6-10, 18-25 mm - l n g; Pd sessile, linear- 

 oblong, nearly glabrous, veined, 4-8 cm. long. Beaches, N. J. to arctic Am., the 

 Great Lakes, and on the Pacific coast. Also in Europe and Asia. May-Aug. 



2. Lathyrus venosus Muhl. VEINY PEA. (L F. f. 2216.) Finely pubescent 

 or glabrous, perennial, 6-9 dm. long. Stems 4-angled; stipules lanceolate, half- 

 sagittate, acute or acuminate, 8-25 mm. long; leaves petioled; leaflets 4-7 pairs, 

 ovate or oval, mucronulate, often reticulated, mostly rounded at the base, 2.5-5 cm - 

 long; tendrils branched; peduncles shorter than the leaves; flowers 12-16 mm. 

 long; pod linear, sessile, glabrous, veined, 4-8 cm. long. River shores and banks, 

 N. J. and Penn. to Ind., Assiniboia, Ga., La. and Kans. May-July. 



3. Lathyrus palustris L. MARSH VETCHLING. (I. F. f. 2217.) Perennial, 

 glabrous or sparingly pubescent; stems slender, 3-6 dm. long; stipules half-sagit- 

 tate, 1-2 cm. long; leaflets 2-4 pairs, lanceolate, oblong or linear-oblong, acute or 

 obtusish and mucronate, 2.5-6 cm. long; tendrils branched; peduncles generally 

 about equalling the leaves; flowers 1-1.5 cm< l n g; Pd linear, sessile, slightly 

 pubescent or glabrous, 4-6 cm. long. In moist or wet grounds, Lab. to Alaska, 

 Mass., N. Y., S. Dak. and Br. Col. Also in Europe and Asia. May-Aug. 



4. Lathyrus myrtifolius Muhl. MYRTLE-LEAVED MARSH PEA. (I. F. f. 

 2218.) Perennial, usually glabrous; stems angled, 3-9 dm. long, weak. Stipules 

 obliquely ovate or half -sagittate, 12-25 mm - l n g> toothed ; leaflets 2-4 pairs, 

 mostly 3 pairs, oval, oval-oblong or ovate, mucronate, narrowed at the base, 

 1.8-5 cm - l n g> rather thin; tendrils branched; peduncles equalling the leaves or 

 shorter. 3~9-flowered; flowers similar to those of the preceding; pod linear, glab- 

 rous, sessile, 2.5-5 cm - lon g- I n moist or wet grounds, N. B. to Manitoba, N. 

 Car. and Tenn. May-July. 



Lathyrus myrtifplius macranthus White. Pubescent; stipules larger, often half as 

 large as the leaflets; flowers 2-2.5 cm - long- Me. 



