LEGUMINOS^E. ( x PULSE FAMILY.) 95 



8. DALEA, L. DALEA. 



Calyx 5-cleft or toothed. Corolla imperfectly papilionaceous : petals aB on 

 claws : the staniard heart-shaped, inserted in the bottom of the calyx : the keel 

 and wings borne on the middle of the monadelphous sheath of filaments, which 

 is cleft do\\n one side. Stamens 10, rarely 9. Pod membranaceous, 1 -seeded, 

 indehiscent, enclosed in the persistent calyx. Mostly herbs, more or less dotted 

 with glands, with minute stipules, the flowers in terminal spikes or heads. 

 (Named for Thomas Dale, an English botanist.) 



1. D. alopecuroicles, Willd. Erect (l-2high), glabrous, except 

 the dense and cylindrical silky-villous spike ; leaves pinnate, of many linear- 

 oblong leaflets ; corolla small, whitish. Alluvial soil, Illinois and south- 

 ward. July. (Numerous species occur farther southwest.) 



9. PETAJLOSTEMON, Michx. PRAIRIE CLOVER. 



Calyx 5-toothed. Corolla indistinctly papilionaceous : petals all on thread- 

 shaped claws, 4 of them nearly similar and spreading, borne on the top of the 

 monadelphous and cleft sheath of filaments, alternate with the 5 anthers ; the 

 fifth (standard) inserted in the bottom of the calyx, heart-shaped or oblong. 

 Pod membranaceous, enclosed in the calyx, indehiscent, 1 -seeded. Chiefly 

 perennial herbs, upright, dotted with glands, with crowded odd-pinnate leaves, 

 minute stipules, and small flowers in very dense terminal and peduncled heads 

 or spikes. (Name combined of the two Greek words for petal and stamen, 

 alluding to the peculiar union of these organs in this genus.) 



1. P. violaceus, Michx. Smoothish; leaflets 5, narrowly linear, 

 heads globose-ovate, or oblong-cylindrical when old ; bracts pointed, not longer 

 than the silky-hoary calyx ; corolla rose-purple. Dry prairies, Michigan, Wis- 

 consin, and southward. July. 



2. P. Candidas, Michx. Smooth; leaflets 7-9, lanceolate or linear- 

 oblong; heads oblong, when old cylindrical; bracts awned, longer than the 

 nearly glabrous calyx ; corolla white. Wisconsin to Kentucky and westward. 

 July." 



10. AMOR P HA, L. FALSE IXDIGO. 



Calyx inversely conical, 5-toothed, persistent. Standard concave, erect : the 

 other petals entirely wanting! Stamens 10, monadelphous at the very base, 

 otherwise distinct. Pod oblong, longer than the calyx, 1 - 2-secdcd, roughened, 

 tardily dehiscent. Shrubs, with odd-pinnate leaves ; the leaflets marked with 

 minute dots, usually stipellate. Flowers violet, crowded in clustered terminal 

 spikes. (Name, a/nope^)//, icanting form, from the absence of 4 of the petals.) 



1. A. fruiicosa, L. (FALSE IXDIGO.) Rather pubescent or smoothish; 

 leaflets 8-12 pairs, oval, scattered; pods 2-seeded. River-banks, S. Penn. to 

 Wisconsin and southward. June. A tall shrub : very variable. 



2. A. canescens, Nutt. (LEAD-PLANT.) Low (l-3 high), whitened 

 with hoary doicn ; leaflets 15-25 pairs, elliptical, crowded, small, the upper 



