Opuntia. CACTACE.E. 247 



angular, variously colored: largo purple flowers open only in sunlight: ovary and 

 fruit with 25 to 30 spiny areola;, 15 to 20 upper sepals, and as many lance-oblong 

 petals: stigmas about 12, erect. — Am. Jour. Sci. 2 ser. xiv. 338; Cact. of Pacif. 

 R. Pep. iv. 35, t. 5, fig. 4 - 10. 



From the eastern slopes of the Southern Sierra Nevada, at San Felipe, into Arizona and Utah, 

 apparently abundant, Parry, 'Newberry, Palmer, and others. Heads usually 4 to 6 together, 5 to 

 lu inches high, 2 or 3 thick ; outer spines \ to j, inner 1 or 2 inches long ; flowers 2J to 3 inches 

 long and wide, appearing in June. 



§2. Prismatic or cylindric, mostly branching: flowers usually longer than wide: 

 stigmas whitish : seeds obovale, usually smooth or pitted : embryo with foli- 

 aceous curved cotyledons. — EuCEEEUS. 



* Ovary and fruit spiny. 



2. C. Emoryi, Engelm. .Stems erect, branching from the base, cylindric, with 

 1G to 20 ribs, closely set with prominent hemispherical areolae bearing numerous 

 (30 to 50) thin straight yellow spines ^ to 1 or 1^ inches long; the 3 to U inner 

 ones longer and deflexed : flowers short, greenish yellow, crowded on one side of the 

 top of the stems : ovary with few short spines, which become formidable upon the 

 subglobose fruit. — Am. Jour. Sci. 1. c. ; Cact. Mex. Bound. 40, t. 60, tig. 1-4. 



On the gravelly mesas near the sea-shore at San Diego {Parry, jlgassiz, Hitchcock), and quite 

 abundant on rocky hills from Los Angeles to the Salinas Valley (Brewer), and into the Peninsula 

 to Kosario, Gabb. Stems 2 to 4 feet high, 1A to 2 inches thick, often from a prostrate rooting 

 base, and forming dense thickets ; areola! 2 lines wide and 3 or 4 lines apart, densely covered 

 with the thin sharp and very brittle spines ; flowers usually on one side only, like those of § Pilo- 

 ccrcus, 1\ to 1J inches long and a little less wide ; fruit about an inch long; seeds over a line 

 long, shining, minutely tuberculate. 



* * Ovary and fruit scaly. 



C. gicanteus, Engelm., 15 to 30 or even 40 feet high, very stout, with few erect branches 

 towards the upper part, cream-white short-tubed flowers, and large oval edible fruit, which at 

 maturity bursts irregularly, and 



C. Thukbert, Engelm., 10 to 15 feet high, more slender, with many equally high ascending 

 branches from the base, similar flowers, and larger globose delicious fruits, are found in the 

 adjoining territories of Arizona and Lower California, and may be looked for in this Stale. 



§ 3. Tall, cylindric, mostly unbranched ; upper flower-bearing portion, with more 

 crowded areola- and lonffer <l,„ser thinner bristly or hairy spines: flowers 

 short : seeds as in the last. — Pilocekeus. 



C. SOHOTTir, Engelm., 4 to 10 feet high, Hie lower part 5 -angled, with distant areola' and few 

 very short and stout spines ; the upper flowering portion deeply .".-ribbed, with close-set areola; 

 bearing num. roils setaceous spines, almost billing the small Mow. is and small berries, — from 

 the saiin: localities as the last two species, — may also be found in Southern California. 



4. OPUNTIA, Tourn., Miller. 



Tube of the flower very short, cup-shaped. Petals spreading or rarely erect. 



Ovary with bristle-bearing ai he in the axils of small tereto deciduous sepals. 



Berry succulent or sometimes dry, marked with bristly or spiny areolae, truncate 

 with a wide umbilicus. Seeds large, white, compressed, with the embryo coiled 

 around the albumen : cotyledons largo, foliaccous. — Articulated much-branched 

 plants, id' various shapes, low and prostrate, or ereel ami shrub-like : young branches 

 with small terete subulate early deciduous loaves, ami in their axils an areola with 

 numerous short easily detached bristles ami, usually, stouter spines, all barbed. 

 Flowers on the joints of the previous year, on tin- same areola; with the spines, 

 mostly large, open only in sunlight. Fruil often edible, often lai 



