118 BOTAirS". 



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, (2 J' 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.) 



Ceeeus vieidiflokus, Eng. With very short pectinate pale and reddish- 

 brown spines and small green flowers. — Common in Colorado, and may be 

 found in Utah. 



Opxjntia^ (Platopuntia) basilaeis, 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, 2 J' 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^eocaepa, Eng. & Big., Var. (?) 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 Missoueiensis, 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. Frorh 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' 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.) 



^ OPUNTIA, TouEN. Sepals and petals ■united beyond the sepal-ljearing 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. 



J Cylindbopuntia, Eng. Joints clavate or cylindrical ; embryo nearly circular. 



