Vor. II.] PEA FAMILY. 331 
4. Lathyrus myrtifolius Muhl. Myrtle-leaved Marsh Pea. (Fig. 2218.) 
Lathyrus myrtifolius Muhl.; Willd. Sp. Pl. 3: 
Iogt. 1803. : 
Lathyrus palustris var. myrtifolius A. Gray, 
Man. Ed. 2, 104. 1856. 
Perennial, usually quite glabrous; stems 
slender, angled, not winged, 1°-3° long, 
weak. Stipules obliquely ovate, or half- 
sagittate, 6//-12’’ long, often 4//-6’’ wide 
and toothed; leaflets 2-4 pairs, mostly 3 pairs, 
oval, oval-oblong or ovate, mucronate and 
acute or obtuse at the apex, narrowed at the 
base, 9//-2’ long, 3/’-7’’ wide, rather thin; 
tendrils branched; peduncles equalling the 
leaves, or shorter, 3-9-flowered; flowers pur- 
ple or purplish, similar to those of the pre- 
ceding species; pod linear, glabrous, sessile, 
1/-2/ long, 334’ wide or less. 
In moist or wet grounds, New Brunswick to 
Manitoba, south to North Carolina and Tennes- 
see. May-July. 
Lathyrus myrtifolius macranthus White, Bull. 
Torr. Club, 21: 448. 1894. 
Pubescent; stipules larger, often half as large 
as the leaflets; flowers 10'’-12'’ long. Maine. 
5. Lathyrus decaphyllus Pursh. 
Prairie Vetchling. (Fig. 2219.) 
L. decaphylius Pursh, Fl. Am. Sept. 471. 1814. 
Lathyrus polymorphus Nutt. Gen. 2:96. 1818. 
Perennial, erect or ascending, glabrous, 
or finely pubescent, 6/-18’ high. Stems 
angled; stipules half-sagittate, acuminate, 
4//-12/ long, 1//-3/’ wide; leaves petioled; 
leaflets 3-7 pairs, obtuse or acute and 
mucronulate at the apex, narrowed at the 
base, thick, conspicuously reticulated, 1/— 
2%’ long, 3//-8/’ wide; stipules when 
present, branched, but often wanting: 
peduncles usually shorter than the leaves; 
flowers purple, 1/-114’ long, showy; pod 
linear, stipitate; seeds with a narrow stalk 
and short hilum, 
Kansas (?), Idaho and Colorado to Arizona 
and New Mexico. March-July. 
6. Lathyrus ornatus Nutt. Showy Q 
'  Vetchling. (Fig. 2220.) S 
Lathyrus ornatus Nutt.; T. & G. Fl. INAS, Zs 
277. 1838. . 
Closely resembling the preceding species, 
but generally lower, often less than 1° high. 
Stipules lanceolate or linear, 2’/-10’’ long; 
leaflets narrow, linear or linear-oblong, acute 
and mucronate, 4’’-12’’ long, 1’/-2’’ wide; 
tendrils commonly wanting; flowers purple, 
showy, I’-1!4’ long; pod linear, stipitate; 
seeds with a broad stalk and long hilum. 
WW 
j 
\ 3 
Indian Territory to Kansas and Dakota, west \\\\ i 5 
W/ NWN 
to Colorado and Utah. May-June. \ 
