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3. §. vesicaria Ell. A tall smooth-branching annual: leaflets numerous, oblong- 
linear: racemes 4 to 8-tlowered, often compound: flowers yellow: pod elliptical- 
oblong, compressed, acute at each end, stipitate, 1-celled and 2-seeded, the outer 
coriaceous portion at length falling away and leaving the seeds inclosed in the thin 
white inner membrane. (Glottidium Floridanum Desv.)—Extending from the Gulf 
States into southern Texas. 
22. ASTRAGALUS Tourn. (MILK VETCH.) 
Chiefly herbs, with odd-pinnate leaves, spiked or racemed flowers, a 
narrow and erect standard, keel not tipped with a point or sharp ap- 
pendage, and turgid or inflated pods with one or both the sutures 
turned in, sometimes dividing the cell lengthwise into two.—A very 
large and difficult western genus, not very numerously represented in 
Texas. Mature pods are usually necessary for certain identification of 
the species. 
I, Pod turgid, completely or imperfectly 2-celled by the intrusion of the dorsal suture, 
the ventral suture being not at all or less deeply inflexed. 
* Pod plum-shaped, succulent, becoming thick and fleshy, indehiscent, not stipitale, com- 
pletely 2-celled. 
1. A. caryocarpus Ker. (GROUND PLUM.) Pale and minutely appressed-pubes- 
cent: leaflets narrowly oblong: flowers in a short spike-like raceme; corolla violct- 
purple: pod glabrous, ovate-globular, more or less pointed, about 16 mm. in diameter, 
very thick-walled, cellular or corky when dry.—A species of the western plains and 
extending into Texas as far south as the San Antonio. 
2, A. Mexicanus A. DC. Smoother, or pubescent with looser hairs, larger: leaf- 
lets rovndish, obovate, or oblong: flowers larger, 20 to 24 mm, long: calyx softly 
hairy: corolla cream-color, bluish only at tip: pod globular, very obtuse and point- 
less, 2.5 cm. or more in diameter: otherwise like the last.—Prairies throughout 
Texas. 
2 A. Plattensis Nutt. Loosely viilous: stipules conspicuous: leaflets oblong, 
often glabrous above: flowers crowded in a short spike or oblong head, cream-color 
often tinged or tipped with purple: pod ovate, pointed, and villous (as is the calyx).— 
A species of the plains extending into northern Texas. 
* * Pod dry, coriaceous, cartilaginous or membranous, dehiscent. 
+ Pod completely 2-celled. 
++ Pod sessile. 
4. A. mollissimus Torr. Stout, decumbent, densely silky-villous throughout and 
tomentose: leatlets 19 to 29, ovate-oblong : peduncles elongated : spikes dense, with 
rather large violet flowers, 12 to 24 mm. long: pod narrow-oblong, 10 to 18 mm. long, 
glabrous, somewhat obcompressed and suleate at both sutures, at length incurved.— 
High prairies and mesas in northwestern Texas and west of the Pecos. The most 
common “loco” plant, and said to be very poisonous to cattle. 
5, A. Bigelovii Gray. Very near the last, but more strictly acaulescent, more 
villous, and especially distinguished by its turgid and very woolly pods in which the 
sutures gre not sulcate.—West of the San Pedro, and extending into Mexico and 
New Mexico. 
6. A. giganteus Watson. Stems stout and erect, 6 to 9 dm. high or more, tomen- 
tose; leaflets 11 to 21, oblong-ovate, acute, villous-pubescent and subtomentose, 12 
to 18 mm. long; stipules broad: racemes short and rather few-flowered, erect, pe- 
dunculate: pod coriaceous, ovate, acuminate, somewhat compressed and the ventral 
guture impressed, erect, 18 mm. long.—At Fort Davis, western Texas (Havard.) 
