228 CACTACEZ OF CLARENCE KING’S EXPLORATION. 
is also the ovary. Flowers large, 2} inches in diameter, purple ; fruit dry, with large and thick seeds. — Nevada, in 
the Silver Peak region south of Walker’s Lake (Gabb), and southward 
O. SPHZROCARPA, Engelm. & Bigelow, var. (7?) Uranensis, Engelm. Prostrate; joints small, orbicular-ovate, 
2-3 inches long and nearly as wide, thick. Spines in the axils of the minute subulate leaves, few and mostly weak or 
solitary or none, with few and very short bristles. Flowers 3 inches in aig pale yellow ; fruit oval, almost 
spineless, at last dry. — In the pass west of Steptoe Valley, Utah (H. Engelm 
. Missouriensis, D.C. Prostrate; joints medium-sized, obovate or ae orbicular, tuberculate; leaves 
Sintibe, subulate, all bearing in their axils 5-10 radiating or deflexed spines, 1-2 inches long, often with a few erect 
darker ones. Flower large, 3 inches broad, yellow ; ovary and dry fruit spiny. — Quite variable, especially in the 
stoutness and color of the spines. From the upper Missouri to the Canadian and New Mexico, and throughout the 
Salt Lake basin. [Found in Salt Lake Valley and the Wahsatch, 4,200-6,500 feet altitude. July in flower. Joints 
sometimes 6 inches long and 4 inches broad. s.w.] (434.) 
O. HysTRictna, Engelm. & Bigelow. Very similar to the preceding, and probably only a form of it, with [119] 
longer and more numerous gray or reddish spines, longer yellow bristles, and usually smaller flowers. — New 
Mexico ; between Walker and Carson rivers (H. Engelmann), and Owen’s Valley (Gabb), Nevada. [Found abun- 
dantly in Monitor and Thousand Spring valleys, Nevada, 5,000-6,000 feet altitude. July in flower; September in 
ruit. Flowers either purple or sulphur-yellow, scarcely smaller. s. w.]. (436.) 
O. ruTILA, Nutt. Similar to 0. Missouriensis ; joints often larger, 3 inches by 4 inches, covered with prenios set 
bunches of mostly radiating and deflexed spines, the larger ones flattened and often twisted. Flowers rose-red ; 
and dry berry spiny. — From Fillmore to St. George, Utah (Dr. aa J. E. Johnson). A rediscovery of Nuttall 
long-lost plant, who found it near the Green River in southern Wyomin 
O. ERINACEA, Engelm. & Bigelow. Pacif. R. R. Surv., 4. 47, tab. 13. Diffuse, ascending ; joints thick, ovate, 
2-25 inches long, or sometimes elongated and almost cylindric, densely covered with clusters of 3-5 radiating spines, 
slender, $-14 inch long, very rigid, reddish-gray, with 2-4 smaller ones below; berry ovate, 1} inch long, with 
crowded clusters of 12-20 mostly deflexed spines, 3-6 lines ste — Near Mohave Creek, southern California (Bigelow). 
[A specimen in Herb. Gray., collected by Dr. Bloomer near Virginia City, Nevada (not seen by Dr. Engelmann), 
may belong to this species. s. w.] 
O. FRAGILIS, Nutt. Joints small, ovate, compressed or tumid or even terete, 1-1} inch long, fragile ; larger 
spines 4, cruciate, mostly yellowish brown, with 4-6 smaller white radiating ones below ; bristles few. Flowers 
smaller, yellow ; fruit smaller, with 20-28 clusters of bristles, only the upper ones with a few short spines ; seeds few, 
regular. — On the upper Missouri and Yellowstone, southward probably to New Mexico. [Found at the west base of 
the Wahsatch, in Jordan Valley. Specimens not seen by Dr. Engelmann, but doubtless of this species, s.w.] (437.) 
O. (CYLINDROPUNTIA) PULCHELLA, Engelm. Low, 3-10 inches high, spreading. Joints small, slender, 1-3 inches 
i 6 lines thick, clavate, tuberculated, with bunches of — _ spines 6-18 lines long, from white to 
early black, one or more of the inner longer ones flattened. Flow e, 14 inch or less in diameter ; ovary and 
ies berry bearing numerous flexible, not barbed bristles. — ae Walker 8 ia Nevada (H. Engelmann, Ga 
[Frequent in the valleys of western Nevada from the Trinity Mountains to Monitor Valley, 4,000-5,000 feet [120] 
altitude; May—August. A very showy species, with sometimes 50 flowers upon a single plant ; main stem 
erect, becoming 9 lines in thickness, and occasionally showing 25 annual rings. 8. W.] (438.) 
O. ARBORESCENS, Engelm. 3-5 feet high or more, with horizontal branches, cylindric, strongly rN 
joints, numerous sheathed spines, large purple flowers, and tuberculated unarmed fruit.— New Mexico and Arizo 
and probably farther northward. 
- ACANTHOCARPA, Engelm. & Bigelow. Similar to the last; rather more slender, and with more erect 
branches, smaller copper-colored flowers, and rather even, spiny fruit. — Arizona, and probably southern Utah. 
O. rruTEScEeNs, Engelm. 2-4 feet high, with slender terete joints 3 lines in thickness, very small yellow 
flowers, and scarlet berries. — From Texas to southeastern California, and probably farther northward.t 
1 For the Borayy or CaLtrornta, by W. H. Brewer and 
Sereno Watson, Dr. Engelmann contributed the article Cae- 
tacee. But as all but one of the species had at been 
published, only this one is here inser py Ep1 
MAMILLARIA ARIZONICA, n. § dia eee 
ovate; tubercles den-cytindrieal senting asc growed 
bearing numerous straight, rigid spines; the 
terior spines whitish, 3 to 6 interior rae at peat a. 
above ; flowers large, rose-colored ; sepals 30 to 40, linear- 
subulate, fimbriate ; age 40 to 50, lance-linear, curved ; 
stigmas 8 to 10, ; berry oval, green, with obovate, 
compressed, pitted, ar beh seeds, 
sandy and rocky soil in northern Arizona, from the Colo- 
oer eastward (Cones, Palmer, F. Bischoff), and into southern 
h (J. E. John ~ probably in southeastern California. 
‘a rger in all its parts than M. phet losperma, 3 or 4 inches 
thick ; tubercles an inch long; spines 5 to 15 ee long 5 
flowers 2 to 24 inches wide, very showy. — Vol. I. p. 244. 
