118 
BOTANY. 
spines, 3-6" long, and about 4 darker (yellow, brown or black) stout and an¬ 
gular, straight or curved, central ones, 1-3' long; flowers very numerous, 
large, (2J' broad or more,) purple, diurnal.—From Salt Lake Desert (H. 
Engelmann) to Silver Peak in the Sierras, (Grabb,) and southward to South¬ 
ern Utah (Johnson) and the Mohave country (Bigelow.) 
Cereus viridiflorus, Eng. With very short pectinate pale and reddish- 
brown spines and small green flowers.—Common in Colorado, and may be 
found in Utah. 
Opuntia 1 (Platopuntia) basilaris, Eng. & Big. Low; joints 5-8' 
long, obovate or triangular, proliferous from their base, pubescent, unarmed, 
but beset with numerous dense fascicles of short brownish bristles, as is also 
the ovary; flowers large, 2J' in diameter, purple; fruit dry, with large and 
thick seeds.—Nevada, in the Silver Peak region south of Walker’s Lake, 
(Gabb,) and* southward. 
Opuntia sph^erocarpa, Eng. & Big., Yar. (?) Utahensis, Eng. Pros¬ 
trate ; joints small, orbicular-ovate, 2-3 / long and nearly as wide, thick; 
spines in the axils of the minute subulate leaves, few and mostly weak or soli¬ 
tary or none, with few and very short bristles; flowers 3' in diameter, pale- 
yellow; fruit oval, almost spineless, at last dry.—In the pass west of Steptoe 
Valley, Utah, (H. Engelmann.) 
Opuntia Missouriensis, DC. Prostrate; joints medium-sized, obovate 
or almost orbicular, tuberculate; leaves minute, subulate, all bearing in their 
axils 5-10 radiating or deflexed spines, 1-2' long, often with a few erect 
darker ones ; flower large, 3' 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 & long and 4' broad, w.] (434.) 
Var. [With smaller creeping joints, the numerous fascicles of short stout 
spines strongly reflexed. Above Wahsatch Station in the Wahsatch Mount¬ 
ains; 7,000 feet altitude, w.] (435.) 
1 OPUNTIA, Tourn. Sepals and petals united beyond the sepal-bearing ovary into a very short 
cup. Berry pulpy or dry. Seeds large, whitish, bony, flat, mostly irregular. Embryo curved around the 
albumen; cotyledons foliaceous, usually contrary to the sides of the seed.—Jointed, the joints broad and 
flat, or clavate or cylindrical, bearing bunches of barbed spines and bristles in the axils of small terete 
deciduous leaves, and from their middle rather large flowers, opening only in sunshine and much wider 
than long. The above species belong to the two sections :— 
§ Platopuntia, Eng. Joints flattened; embryo somewhat spiral. 
§ Cylindropuntia, Eng. Joints clavate or cylindrical; embryo nearly circular. 
Missouri Botanical 
George Engelmann 
Garden 
Papers 
