Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 4, Pt. 3

BOTANY.
INDIGOFERA LEPTOSEPALA, Nutt. in Torr. & Gray, Fl. 1,. 298. With the preceding, and at
Upper Crosstimbers, Indian Territory; August.
PHACA DENSIFOLIA, Smith in Bee8 Cyci.; Torr. & Gray, Fl. 1. p. 344 & 693; Hook. Ic. t. 283.
P. Nuttallii, T. & Gr. 1. c. Cocomungo, California; March 18. Legumes an inch and a half
long, and more than three-fourths of an inch broad. Seeds numerous, not half the size of a
pepper-corn. Our plant differs somewhat from Douglas's, as figured by Ho6ker in his Icones,
especially in being smoother and the flowers larger, as well as in the larger calyx-eeth; but it is
undoubtedly the same.
ASTRAGALUS DIDYMOcARPUS, H~ook. & wArH. Bot. Beech., p.H334, t. 81; Torr. & Graye Fl. 1,
p. 693. Fields near Benicia, and Corte Madera; April 10-23. The specimens are much
smaller than those collected by Douglas, Mr. Rich, and Dr. Parry. The legumes are scarcely
three lines long, and of about the same breadth. When young they are villous,' but nearly
glabrous (though strongly rugose) when old. The leaves vary in breadth from half a line to
two lines or more. We have lIittle doubt that A. nigrescens and A. Catalinensis, rutt. (P1.
-Gamb.,) are varieties of this species.
ASTRAGALUS MISSOURIENSIS, Nutt. Gen. 2, p. 99; Torr. & Gray, Fl. 1, p. 331, excl. syn. Pursh.
Gravelly hills, New Mexico, and on Williams' fork of the Colorado, February 6.
ASTRAGALUS FREMONTII (sp. nov.): -molliter strigoso-cinerea; radice perenni; caulibus adscendentibus (10 poll. longis) crassiusculis; foliolis 9-21 ovalibus vel rotundatis retusis; stipulis
triangulatis basi tantum petioli adnatis; pedunculis folium squantibus, floribus laxiuscule spicatis
patentibus subsessilibus; calycis dentibus subulatis tubo campanulato brevioribus; "corolla
purpurea;" leguminibus immaturis membranaceis inflatis ovatis acuminatis bilocellatis polyspermis estipitatis. Banks of the Rio Virgin; May 3, 1844, Fremont. Var. caule breviori
(2-3-pollicari); floribus majoribus; calyce magis cylindraceo et nigro-hirsuto. On the Mohave
creek; March 3. An early state, only in flower, apparently of the same species as that gathered
in the same region by Colonel Fremont. Leaflets 3-6 lines long. Flowers half an inch long;
the calyx 3 lines long; the corolla apparently white, or whitish; all the petals tipped
with deep violet purple. The half-grown pods of Fremont's specimens are over half an inch
in length, nearly glabrous, very thin, and completely bilocellate.-Gray, Mss.
ASTRAGALUS HUMISTRATUS, Gray, P1. Wright. 5, p. 45. Arroyos, near San Antonita, New
Mexico; October. In fruit.
ASTRAGALUS MOLLISSIMUS, Torr. in A4nn. Lyc., New York, 2, p. 178; Gray, P1. Wright. 1, p. 53.
Rocky ridges of the False Washita, August; and plains of the Upper Canadian, September.
In flower.
ASTRAGALUS DIPHYSUS, Gray, P1. Fendl., p. 34. Sandy places, near Albuquerque; October.
In fruit.
ASTRAGALUS (PHAcA) LONCHOCARPUS. Phaca macrocarpa, Gray, P1. Fendl., p. 36. Bluffs and
rocky places, on the Llano Estacado; September. The few specimens of this interesting plant
bear only old and dehiscent pods, which are shorter than in Fendler specimens, and are follicular,
opening as they do only by the ventral suture, and at length spreading ut into a perfectly
plane lamina. The leaflets are nearly all wanting, and the filiform naked petioles are rather
persistent. The root is perennial. The name has to be changed, on account of the Astragalus
macrocarpus of De Candolle.
OXYTROPIS URALENSIS, I)CJ. Prod. 2, p. 276; Hook. Fl. Bor.-Am. 1, p. 145. Sandia mountains, New Mexico; October. In flower and fruit.
OXYTROPIS LAMBERTI, Pnrsh Fl. 2, p. 740. Rocky hills, of the Upper Canadian; September.
Narrow-leaved and loosely-flowered forms. Pods slender and very minutely silky-puberulent;
in one specimen of which the flowers are unknown, shorter and thicker, and strigose-hirsute.
OXYTROPIS SERICEA, Nn~tt. in Torr. & Gray, Fl. 1, p. 339. Bluffs and rocky places, on the
Llano Estacado; September. There is scarce a doubt that this passes into O. Lamberti.
KENTROPHYTA MONTANA, Ntutt. i Torr. & Gray, Fl. 1, pi 353. Inscription Rock, New Mexico;
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