60 



LEGUMINOS.E. f PULSE FAMILY.") 



13. ASTRAGALUS, Tourn. Rattle-weed. 



Corolla and its slender-clawed petals usually narrow. — Herbs, or a few 

 woody at base : with rather small flowers, chiefly in simple axillary spikes or 

 racemes : the peduncle commonly elongated. — Gray, Proc. Am. Acad. vi. 188. 

 Watson, Bot. King's Exp. 435. 



Series I. Pod completely or imperfectly 2-celled by the intrusion of the dorsal 

 suture, the ventral suture being not at all or less deeply inflexed. — Astra- 

 galus, L. 



Artificial Key. 



i>od succulent, becoming thick and fleshy, sessile Nos. 1, 2, 3 



Pod not 2-celled, inflated, not mottled, sessile ; plant liirsute-canescent ... 27 



Pod completely 2-celled, bladdery-inflated, often mottled, sessile ; plant nearly glabrous 4 

 Pod coriaceous, cartilaginous, or chartaceous, not bladdery-inflated, 



1. Conspicuously stipitate, the stipe about equalling or surpassing the calyx, 



Not sulcate 20, 21 



Deeply sulcate. 



Pod glabrous, pendent .... 14, 15, 1G 



Pod black-hairy 24 



2. Short-stipitate, 



Not sulcate . 22 



Sulcate, 



Incurved, mottled 25 



Straight, 



Completely 2-celled 11, 13 



Incompletely 2-celled 23, 26 



3. Sessile. 



Completely 2-celled, 



Glabrous . 5, 7 



Pubescent or hoary 8, 9, 10, 12 



Villous or woolly 6 



Incompletely 2-celled. 



Stems a span or more high . 18, 19 



Stems not rising so high, or none at all 



Pod straight or nearly so .... 17, 28 



Pod curved ... 29, 30, 31, 32 



Systematic Synopsis. 



§ 1. Pod plum-shaped, succulent, becoming thick and fleshy, indehiscent, not stip- 

 itate, completely 2-celled. — Perennials,, with low leafy stems : stipules distinct, 

 nearly free : racemes short, spike4ike. 



* Ovary and pod glabrous. 



1. A. caryocarpus, Ker. Grayish with an a ppressed pubescence : flowers 

 violet: pod globose or ovate, usually pointed. — Plains from the Saskatchewan 

 to Texas. 



2. A. Mexicanus, A.DC Taller, greener, less pubescent: flowers lighter- 

 colored or white: calyx softly white-villons or tomentose : pod ovate-globose, 

 scarcely pointed. — From Colorado to Missouri and S. Texas. 



* * Ovary hoary-hirsute : pcd sometimes becoming glabrate. 



3. A. Plattensis, Xutt. Loosely villous : flowers ochroleucous or pur- 

 plish above: pod ovate, acuminate, or oblong and somewhat curved. — From 

 Colorado to Nebraska and Illinois, and southward to Texas and X. Alabama. 



