Vou. IL] PEA FAMILY. 305 
2. Phaca neglécta T. & G. Cooper’s Milk Vetch. (Fig. 2149.) 
Phaca neglecta T. & G. Fl. N. A. 1: 344. 1838. 
Astragalus Cooperi A. Gray, Man. Ed. 2, 98. 1856. 
Glabrous or nearly so, erect, 1°-2° high. Stipules 
ovate, acute, 1’’/-2’’ long; leaflets 9-21, thin, oblong or 
elliptic, often minutely pubescent beneath, 8//-12/ long, 
obtuse or emarginate at the apex, narrowed at the base; 
peduncles shorter than or equalling the leaves; flowers 
white, 5’’-7’’ long, in rather loose spikes; calyx pubes- 
cent with blackish hairs, its teeth subulate; pod 1-celled, 
sessile, the ventral suture somewhat intruded, inflated, 
coriaceous, oyoid, acute, glabrous, slightly furrowed along 
both sutures, 6’/-10’’ long, 5/’-6’’ thick. 
On banks and shores, Quebec to Niagara, west to Minnesota 
and Iowa. June-July. 
3. Phaca longifolia (Pursh) Nutt. Long- 
leaved Milk Vetch. (Fig. 2150.) 
Psoralea longifolia Pursh, Fl. Am. Sept. 741. 1814. 
Phaca longifolia Nutt.; T. & G. Fl. N. A. 1: 346. 1838. 
Astragalus pictus var. filifolius A. Gray, Proc. Am. Acad. 6: 
215. 1864. 
Erect, very slender, branching, finely canescent, 6-18’ 
high. Stipules subulate, rigid, those of the lower part of 
the stem connate; leaflet usually 1, narrowly linear, nearly 
terete, 1/-4/ long, 1%4’/-1’’ wide, sometimes 3 or 5; flowers 
few, pink, 3//-5’’ long, in short loose racemes; peduncles 
much shorter than the leaves; pod 1-celled, short-stalked, 
much-inflated, membranous, spotted, glabrous, ovoid, 
short-pointed, not furrowed, about 1/ long, 14’ thick. 
In sandy soil, Nebraska to New Mexico. Leaves persistent. 
May-June. 
25. HOMALOBUS Nutt.; T. & G. Fl. N. A. 1: 352. 1838. 
Perennial herbs, with pinnate simple or pinnately 3-5-foliolate leaves, and racemose 
mostly small flowers, the peduncles short, or elongated. Keel of the corolla obtuse. Pod 
flat, glabrous or pubescent, completely 1-celled, few-several-seeded, the sutures both promi- 
nent externally. [Greek, regular-lobes. ] 
Besides the following species, some 30 others occur in western North America. 
Plants leafy-stemmed. 
Leaves pinnate; leaflets 11-23, thin. 1. H. tenellus. 
Leaves pinnate; leaflets 3-7, rigid, very narrow, spiny. 2. H. montanus. 
Plant scapose; leaves simple, or pinnately 3-5-foliolate, the leaflets very narrow. 3. H. caespitosus. 
1. Homalobus tenéllus (Pursh) Britton. 
Loose-flowered Milk Vetch. (Fig. 2151.) 
Astragalus tenellus Pursh, Fl. Am. Sept. 473. 1814. 
Ervum multiflorum Pursh, Fl. Am. Sept. 739. 1814. 
Homalobus multifiorus Tv. & G. Fl. N. A. 1: 351. 1838. 
A. multifiorus A. Gray, Proc. Am. Acad. 6: 226, 1864. 
Ascending or diffuse, slender, branched, finely pubes- 
cent, or glabrate, 10’-18’ high. Stipules broadly ovate, 
144/’-3’’ long, acute or obtuse, the upper ones connate; 
leaflets 11-23, thin, oblong, linear-oblong or oblanceo- 
late, obtuse at the apex, narrowed at the base, 6//—10/’ 
long; flowers yellowish-white, 3/’-4/’ long, in loose 
spike-like racemes; pod stalked, straight, oblong, acute 
at each end, papery, glabrous, 6’’-8’’ long, 2’’ wide. 
Dry soil, Nebraska and Colorado to California, north to 
the Northwest Territory and British Columbia. May-Aug. 
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