

Leguminaceae 241 
LATHYRUS PEA 
Herbs, erect to vining. Leaves pinnate, mostly with tendrils. Flowers solitary or in 
racemes. Calyx oblique or gibbous at base; calyx-teeth nearly equal or the upper ones 
somewhat shorter than the lower. Corolla as in Vicia but usually larger. Stamens diadel- 
phous in groups of 9 and 1, or monadelphous below. Ovules generally numerous: style 
curved; flattish, hairy along its inner side. Pod flat or sometimes terete, 2-valved, dehis- 
cent. (Gk. lathyros—=the name of some plant of this family.) e 
A. Plant densely silky-villous; rachis of leaves without tendrils. W. 
L. littoralis Endl. (Shaggy Pea) 
AA. Plant not villous, either glabrous or pubescent; rachis of. leaves mostly with ten- 
drils or their rudiments. 
B. Flowers purple or whitish. 
C. Stipules narrow, half-sagittate, their lobes usually lanceolate, acuminate; plants 
glabrous or pubescent. 
D. Leaflets 6—14 mm. long, pubescent. 
EF. Peduncles 1—2-flowered; stem very slender. W. 
L. torreyi Gray (1-flowered Pea) 
FE. Peduncles 4—6-flowered; stem rigid. W. 
L. vestitus Nutt. 
DD. Leaflets 15-25 mm. or more long, glabrous or hairy. 
F. Leaflets 2—4, 2.5—8.7 cm. long; peduncles 2-flowered; flowers pur- 
plish, E. (L. sandbergii; L. bijugatus sandbergit. ) 
L. bijugatus White 
FF. Leaflets 4—6 or more, often shorter: either peduncles with 3 or more 
flowers or else flowers white. 
G. Flowers white. 
H. Leaflets 1.4—-2 cm. long. E. 
L. rigidus White 
HH. Leaflets 2.5—7.5 cm. long. 
I. Leaflets linear to linear-lanceolate. E. 
L. cusickii Wats. 
II. Leaflets ovate to ovate-oblong. E. (L. obovatus stipulaceus ; 
L. nevadensis. ) 
L. obovatus White 
GG. Flowers purple. 
ik Stem wingless altho sometimes angular. 
K. Flowers 25 mm. or more long, 3—5 ona peduncle. E. 
L. decaphyllus Pursh (Prairie Pea) 
KK. Flowers 10—20 mm. long, often more than 5 on a peduncle. 
L. Plant glabrous thruout or merely minutely papillose. 
M. Peduncles about equaling the leaves; leaves not thick nor 
coriaceous. U., 
L. bolanderi Wats. 
MM. Peduncles much shorter than the leaves; leaves thick- 
coriaceous. W. E. 
L. coriaceus White 
Le Plant pubescent. 
N. Leaflets lanceolate, pubescent on both sides, obtuse. E. 
L. oregonensis White 
