LATHYRUS. XL VII. LEGUMINOS^E. 219 



* * Corolla not papilionaceous. 



$ Unarmed and glabrous Darlingtonia. 40 



( Corolla regular. \ Armed with uncinate spines Schrankia. 39 



Herbs. { Corolla irregular. Cassia, 35 



Shrubs. Corolla regular Mimosa. 38 



(unarmed. Gymnocladus. 36 



Trees armed with triple spines Gleditschia. 37 



SUBORDER 1. PAPIL.IONACEJE. 



Petals papilionaceous, imbricate in aestivation, the upper one exter- 

 nal. Stamens mostly 10 and diadelphous. 



1. LATHYRUS. 



Calyx campanulate, the 2 upper sepals shortest ; stamens 10, dia- 

 delphous (9 and 1) ; style flat, dilated above, ascending, bent at a 

 right angle with the ovary, pubescent or villous along the inside next 

 the free stamen ; legume oblong, several-seeded. Herbaceous, mostly 

 climbing. Lvs abruptly pinnate, of 1 several pairs of leaflets. Petioles 

 produced into tendrils. Peds. axillary. 



1. L. VENOSUS. Muhl. 



St. 4-cornered, naked ; stips. semi-sagittate, lanceolate, very small ; ped. 

 8 16-flowered, shorter than the leaves ; Ifts. 5 7 pairs, somewhat alternate, 

 obtusish, mucronate. % In shady grounds, Can. and U. S. Stem erect, 2 3f 

 high, mostly smooth. Leaflets li 2' long. Peduncles axillary, many-flow- 

 ered, about the length of the leaves. Corolla purple. Legumes flat and nar- 

 row. Jn. Jl. 



2. L. OCHROLEUCUS. Hook. (L. glaucifolius. Beck.} 



St. slender ; ped. 7 10-flowered, shorter than the leaves ; upper segments 

 of the calyx truncate, angular ; Ifts. about 3 pairs, broadly ovate ; stip. semi-cor- 

 date. Tj. A small, delicate species, very rare, in shady places and on river banks, 

 N. J. to Wise. ! N. to the Arctic circle. Stem 2 3f long, leaning or climbing 

 on other plants. Leaflets 1 !' long, f as wide, larger than the stipules. Pe- 

 duncles axillary, shorter than the leaves. Corolla yellowish-white (ochroleu- 

 cous.) Jn. Jl. 



3. L. PALUSTRIS. Marsh Lathyrus. ^ 



St. winged ; stip. semi-sagittate, large, ovate, mucronate Z/fo. in 2 pairs, 

 oblong-ovate, mucronate ; ped. 3 5-flowered, larger than the leaves. 7J. A slen- 

 der climber, found in wet meadows and thickets, N. Eng. to Or. Stem slender, 

 square, broadly winged at the angles, supported by the tendrils. Leaves pin- 

 nate-cirrhose, leaflets broad or narrow-ovate. Flowers drooping, rather large, 

 variegated with blue and purple. Jn. Jl. 



4. L. MARITIMUS. Bw. (Pisum maritimum. Ph.} Beach Pea. 



St. quadrangular, compressed; petioles flat above; stip. sagittate; Ifts. 

 numerous, subalternate, ovate ; ped. many-flowered. A pale green, creeping 

 plant, resembling the common pea, found on sandy shores, N. Y. to Lab., W. 

 to Or. Stem rigid, 1 2f in length. Stipules connate. Leaves ending in a 

 branching tendril, the lower pairs of leaflets largest. Flowers large, blue. Pod 

 hairy. May July. 



5. L. MYRTIFOLITJS. Muhl. 



St. quadrangular, winged, weak andflexuous; stip. semi-sagittate, ovate- 

 lanceolate, acuminate; Ifts. 2 pairs, oblong-lanceolate, acute, mucronate, vein- 

 less ; ped. longer than the leaves, 4 5-flowered. 7J. A little climber, on river 

 banks, Can. to Md. Bobbins. Stem about 3f long. Leaflets 12' long, i as 

 wide. Flowers pale purple. Jl. Aug. 



6. L. LATIFOLIUS. Everlasting Pea. Ped. many-flowered ; Ifls. 2, lanceolate ; 

 joints membranous, winged. 7). A very showy plant for gardens and arbors, 

 native of England. Stem 6f long, climbing, winged between the joints. Flow- 

 ers large, pink, clustered on a peduncle 6 10' in length. Jl. Aug. 



7. L. ODORATUS. Sweet Pea. Ped. 2-flo\vered; Ifts. 2, ovate-oblong; leg. 



19* 



