Herbs, shrubs, or trees, mostly with compound alternate stipulate leaves, and papilionaceous corollas. (For description of a typical flower, see Part I., cap. v.) Stamens usually 10 (rarely 5), monadelphous, diadelphous, or distinct. Fruit a legume.
* Flowers papilionaceous. Stamens monadelphous or diadelphous. + Not climbing or twining. Pod not jointed.
1. Lupi'nus. Leaves palmately-compound, leaflets 7-9. Flowers in terminal racemes. Stamens monadelphous.
2. Trifo lium. Leaves of 3 leaflets. Flowers in heads. Stamens diadelphous.
3. Medica'go. Leaves pinnate, of 3 leaflets. Flowers in axillary spikes or racemes. Pod curved or coiled. Stamens diadelphous.
4. Melilo'tus, Leaves pinnate, of 3 leaflets, the leaflets toothed.
Flowers in slender axillary racemes. Pod wrinkled, 1-2-seeded. Stamens diadelphous.
5. Hosack'ia. Leaves pinnate, of 1-3 leaflets, stipules gland-like, minute. Flowers yellow, often turning reddish, solitary on axillary peduncles hearing each a leafy bract. Pod linear, several-seeded, partitioned between the seeds. - N. W. only.
6. Robin'ia. Trees. Leaves odd-pinnate, often with spines for stipules, and the leaflets with small stipules. Flowers in hanging axillary racemes. Pod margined on one edge. Stamens diadelphous.
7. Astrag'alus. Leaves odd-pinnate, leaflets numerous. Flowers in dense axillary spikes. Corolla long and narrow, the keel not tipped with a sharp point. Pod turgid, one or both sutures (see Part I., section 217) projecting into the cell, thus partially or wholly dividing the cavity. Stamens diadelphous.
8. Oxyt'ropis. Low perennials with very short tufted stems from a hard rootstock, covered with scaly stipules. Flowers nearly as in Astragalus, but the keel is tipped with a sharp appendage. Peduncles scape-like.
9. Glycyrrhi'za. Leaves odd-pinnate, glandular-viscid. Flowers whitish, in axillary spikes, like those of Astragalus. Root long, perennial, sweet. Pods few-seeded, clothed with rough glands or short hooked prickles. - N. W. chiefly.
10. Tephro'sia. Hoary perennials. Stem simple. Flowers yellowishwhite marked with purple, in a terminal dense oblong raceme. Wings coherent with the keel. Pod linear, flat, several-seeded.
11. Psora'lea. Leaves palmate, of 3-5 leaflets. Stamens diadelphous (sometimes monadelphous). Flowers spiked or racemed, mostly bluish, sometimes white. Pod as long as the calyx, 1-seeded. Calyx, pods, etc, usually glandular-dotted. - N.W. only.
12. Amor'pha. Leaves odd-pinnate, of many leaflets, glandular-dotted.
Corolla of one petal only, the standard, enfolding the stamens and style. Flowers violet or purple, in dense terminal spikes. Stamens 10, monadelphous at the base only, distinct above. - N. W. only.
13. Petaloste'mon. Leaves odd-pinnate, crowded, glandular-dotted.
Flowers small, in dense terminal heads or spikes. Corolla hardly papilionaceous. Stamens only 5. Petals on thread-like claws, 4 of them on the tube of filaments, the fifth on the bottom of the calyx. Pod 1-2-seeded. - N. W. only.
+ + Climbing by tendrils at the ends of the leaves.
14. Vicia. Leaves abruptly pinnate, the leaf stalk prolonged into a tendril. Flowers axillary. Style filiform, hairy at the apex. Pod 2-several-seeded. Stamens diadelphous.
15. Lath'yrus. Leaves as in Vicia. Style flatfish, flattened above, and hairy down the side opposite the free stamen. Stamens diadelphous.
+ + + Twining herbs.
16. A'pios. A twining herb, leaves pinnate, of 5-7 leaflets. Keel of the flower slender and coiled inward. Flowers brown-purple, in dense racemes. Stamens diadelphous.
17. Strophosty'les. A twining herb. Leaves pinnate, of 3 leaflets.
Keel long, strongly incurved. Standard recurved-spreading. Style bearded along the upper side. Pod terete. Seeds oblong, pubescent. Stamens diadelphous.
18. Amphicarpae'a. A low and slender twiner, the stem clothed with brownish hairs. Leaves pinnate, of 3 leaflets. Flowers polygamous, those of the upper racemes perfect, those near the base fertile, with the corolla inconspicuous or none. Stamens diadelphous.
+ + + + Pods transversely jointed, the joints reticulated.
19. Desmo'dium. Leaves pinnate, of 3 leaflets. Calyx 2-lipped. Flowers purple or purplish, in axillary or terminal racemes. Pod flat, the lower margin deeply lobed, thus making the pod jointed, roughened with hooked hairs, causing the pods to adhere to the clothing, etc. Stamens diadelphous.
20. Hedys'arum. Leaves pinnate, of numerous leaflets. Calyx 5-cleft.
Pod flat, several-jointed, the joints roundish, reticulated, not rough. Flowers purple, deflexed, in racemes. Stamens diadelphous.
21. Lespede'za. Leaves pinnate, of 3 leaflets. Calyx 5-cleft. Pod flat, oval or roundish, occasionally 2-jointed. but only 1-seeded. Flowers sometimes polygamous. Stamens diadelphous.
* * Flowers papilionaceous. Stamens all separate.
22. Baptis'ia. Leaves palmate, of 3 leaflets. Flowers yellow. Stamens all separate. The keel-petals nearly separate. Racemes terminating the bushy branches. Pods inflated.
23. Thermop'sis. Leaves palmate, of 3 leaflets, and with broad leaflike stipules. Stamens all separate. Flowers yellow. Pod flat, linear, curved. - N. W. only.
* * * Flowers not papilionaceous; polygamous. Trees.
24. Gledit'schia. Thorny trees, with abruptly once- or twice-pinnate leaves. Flowers greenish, inconspicuous, in small spikes. Stamens separate, 3-10.
25. Gymnoc'ladus. Not thorny. Large trees with doubly pinnate leaves, the leaflets vertical. Pod very long and broad. Stamens 10. Petals on the summit of the long calyx-tube, whitish.
1. L. peren'nis, L. (Wild Lupine.) Stem erect, somewhat hairy. Leaflets 7-9, oblanceolate. Calyx deeply 2-lipped. Pods hairy. - Sandy soil.
2. L. argen'teus, Pursh., var. argophyl'lus, Watson, occurs in the far west. The petals are blue or cream-coloured, and the calyx is decidedly spurred at the base. Plant hoary-pubescent.
3. L. King'ii, Watson (L, pusillus, Pursh.), is also a N.W. species. Seeds only 2 or 3. Plant low, villous with white soft hairs. Racemes short, few-flowered, on long slender peduncles.