80 
16. Astragalus montanus (Nutt. in T. & G. Fl. 1 353 (1838) as 
Kentrophyta) Tragacantha montana (Nutt.) Kuntze, A. Kentrophyta 
Gray. Homalobus montanus (Nutt.) Britton, Kentrophyta viridis 
Nutt. This is a very variable species. The type has very rigid stems 
and leaves, the latter nearly sessile and with very spinose and rigid 
channeled rigid leaflets 5-10 mm. long which are linear-subulate, with 
conspicuous, hyaline and spiny stipules. Pubescence attached near the 
middle. Flowers 5-10 mm. long, white with purple keel tip. Banner 
arched to about 90 degrees or less abruptly and with hump below the 
bend, hooded, with very concave sides and little reflexed, th groove 
very narrow, the blade contracted about 2 mm. below the tip so that 
the general outline is oblong, the tip abruptly reflexed or not at all, 
deeply notched, a little wider at tip than below, finely striate-veined 
with purple, white spot evident, broad veined; wings connivent, oblong, 
ovate, to lunate obtuse to barely acute, about 3 mm. longer than 
keel or bearing the same relation when flowers are smaller, ascending 
to nearly 90 degrees. Keel purple-tipped and very sharp and much 
incurved. The right wing folded over the end of the keel. Calyx short- 
campanulate and obconical and Hedeoma-like, with broad sinuses and 
subulate curved teeth about as long as tube which is about 2 mm. 
long, sometimes a little flattened above, obliquely attached. Pods in 
the type obliquely ovate, with short-acuminate tip, hoary, laterally 
flattened, not sulcate, about 4 mm. long. It abounds in mats on the 
bad lands of Wyoming, to S. Dakota mostly on clayey knolls, extend- 
ing over into Dakotah and Colorado and northward to Alberta, and 
southward to northern Airzona and New Mexico. Upper edge of the 
Lower Temperate and lower part of Middle Temperate life zone. 
Astragalus montanus var. Coloradoensis (Jones as Kentrophyta 
var. Cont 10 63 (1902). This is a form with stipules all free and 
small but acerose, white stems, and similar pods 10 mm. long. In the 
hot region of northern Arizona at Lee’s Ferry on the edge of the Tro- 
pical life zone in dry plains. 
Astragalus montanus var. ungulatus. (Jones Cont. 7 650 (1895) 
as Kentrophyta var. This is a very condensed form with leaves hardly 
1 em, long and le^flets about 7 mm. long. Stipules hyaline small and 
not acerose. Flowers about 5 mm. long Pods claw-like oblianely 
ovate, with arched tip and nearly round in cross-section, rarely a 
trifle sulcate, hoary, 3-4 mm. long, mostly single in the axils. Sprice- 
mont Nevada on barren gravelly knolls, Lower Temperate life zone. 
Kentrophyta Wolfii Rydberg is about this form. 
Astragalus montanus. var impensus (Sheldon Minn. Bot. Stud. 9 
118 (1894) as A. viridis var. A. Kemtrophyta var. elatus Watson. 
Kentrophyta impensa (Sheldon) Rydberg. This is an erect form or a 
matted form where some of the central stems are erect and often 2 
feet high, with leaves of the type but mostly shorter, and the small 
flowers and pods of the var, ungulatus, but generally 2 or 3 feet at 
each node and pods sometimes with an elongated falcate: and acerose 
tip and often nearly smooth. This has the widest range of all the 
forms, from Fort Wingate through northern Arizona. the Navaio 
Basin, westward to Pioche and the Sierras, throughout Utah and north- 
westward to Walla Walla in the Columbia Basin, at least in eastern 
Nevada. In the Lower Temperate life zone on dry gravelly mesas, 
mostly among the junipers. 
Astragalus montanus var. rotundus. (Jones Cont. 7 650 (1895) 
as tegetarius var. rotundus.) This is a prostrate straggling form 
with long stems and long internodes mostly, with the small pods 
. and flowers of the var. ungulatus but pods conical, little flattened 
normally straight and with sutures arched and convex and with a tri- 
angular tip, leaflets about 5 mm. long and barely needle-tipped. linear. 
| Flowers light-purple. Among the pine our at the head of the 
| Bet. Utah, Middle T life zone. A Aulas form on the 
