Pea Family. 41 



V. cracca L. Plant pubescent or rarely glabrous; spike-like racemes dense, 

 15— to-flowered; stipules linear, entire, acute; leaflets linear or linear-oblong. 

 Rare; reported from Story county. 



V. caroliniana Walt. Glabrous or nearly so; stipules linear or oblong, en- 

 tire; leaflets oblong, obtuse; peduncles loosely flowered; flowers smaller than 

 the preceding. River banks; rare; reported from Fayette county 

 * * Annual; flowers nearly sessile, 1 or 2 in tlic axils. 



V. angustifolia Roth. Glabrous or puberulent; stipules semi-sagittate, 

 toothed or entire; leaflets linear, lanceolate, or oblanceolate, apex acute, trun- 

 cate, or emarginate, mucronulate; pod linear, 1-2 inches long. One specimen 

 in my collection from Winneshiek county, probably rare, introduced. 



LATHY r^US L. Ours persnnial climbing vines, with pinnate leaves termin- 

 ating in tendrils, and solitary racemose flowers. Calyx eampanulate, 5-tooth- 

 ed, the 2 upper teeth shorter. Wings nearly free. Stamens diadelphous, 9 

 and 1. Style bent at right angles to the ovary, flattish, dilated above, pubes- 

 cent next the free stamen. 



1_. polustris L. Stem smooth or slightly pubescent, winged; stipules large, 

 semi-sagittate, acute; leaflets 2-5 pairs, narrowly oblong to linear; flowers 

 purple. 2—0 to each peduncle, half-inch long. Thickets; June-July; frequent; 

 Fayette, Muscatine, Johnson. Story, Hamilton, Eramet, Lyon, and Page coun- 

 ties. 



L. Venosus Muhl. Stem firm, pubescent or glabrous, 4-angled; stipules 

 small, slender, acute, semi-sagittate; leaflets 5-7 pairs, broadly ovate, obtuse, 

 mucronulate; peduncles shorter than the leaves, 10-U5-fiowered. Wooded 

 hillsides and banks; Ju De-July; frequent; Winneshiek, Fayette, Scott, Floyd, 

 Winnebago. Story, Cerro Gordo, Dickinson, Emmet, and Lyon counties. 



L. ochroleucus Hook. Glabrous, somewhat glaucous; stipules large, folia- 

 ceous, seuii-ovate and semi-sagittate; leaflets 3-5 pairs, ovate or oval, thin, 

 pale beneath; flowers yellowish-white. Borders; May-July; rare; Emmet 

 county, reported from Fayette county. 



APIOS Boerliaave. Ours a perennial vine, with tnilky juice, twining over 

 bushes, bearing edible tubers, with pinnately 5-7-foliate leaves, minute stip- 

 ules, and rather large purplish flowers in axillary racemes. 



A. tuberosa Moench. Flowers in dense short racemes, brown purple, vio- 

 let-scented. Rich soil, moist thickets; July-September; common; Allamakee, 

 Scott, Muscatine, Lee, Johnson, Linn, Story, Emmet, Woodbury, Decatur, 

 Ringgold, Taylor, and Fremont counties. ( A. apios ( L. ) Mac M.) 



STROPHOSTYLES -Ell. Ours annual prostrate or climbing plants, with 

 3-foliate leaves, and flowers in capitate long-peduncled axillary clusters. Ca- 

 lyx 5-toothed, the 2 upper teeth more or less united. Corolla with the inclu- 

 ded stamens and style elongated, incurved. Stamens diadelphous, 9 and 1. 

 Pod linear, elongated, nearly terete or somewhat compressed. 



S. angulosa Ell. Stems 2-6 feet long, branched, retrorsely hairy; leaflets 

 oblong-ovate, with one or the terminal' with two rounded lobes near the base; 

 pod obscurely hairy, terete, 2-3 inches long; seed quadrate, % inch long, trun- 

 cate, pubescent, mealy. Sandy soil; July-September; common. ( S. helveola 

 ( L.) Britton.) 



S. pauciflora (Benth. ) Wats. Low, pubescent; leaflets few, oblong-linear 

 to linear, not lobed; pod pubescent, flattish, 1-1% inches long; seeds as in the 

 last. Sandy soil; August-September; frequent; Muscatine, Wapello, Fremont; 

 Dickinson, and Lyon counties. 



