•2M2 



OPUNTIA 



2601. Opuntia Engelnmnnii. (Xje) 



IS. Engelmannii, Salm-Dyck. Fip. 2601. An erect to 

 SPini-prvx-itrnto. pnifiist-ly branrhiiiK. coarse iilant, 2-5 

 ft. high, forming largo^ iinponetrahlo thickets, usually 

 with a short, more or les.s terete, wooily trintk, with 

 cniyish bark which becomes uiiaruied with age: joints 

 broaiUv obovate to orbicular, pale to bluisli green, very 



variable in size, 

 in large siiecimens 

 12-14 in. long and 

 nearly a.s wide, 

 moderately thick: 

 areoles remote, 

 about 1 in. apart, 

 with gray wool 

 and large, rigid, 

 gray to yellow, 

 unequal bristles: 

 spines mostly 2-4, 

 sometimes 1-3 

 small additional 

 ones, very vari- 

 able, horny, vari- 

 ously colored, 

 mostly yellow, or 

 white w^th reddish 

 base, usually com- 

 pressed or angular 

 and curved or 

 twisted: fls. yel- 

 low, red witliin, fading to red, 2H-3 in. diam.: fr. 

 broadlv pi,Tiform to globose, frequently 2 in. diam., 

 dark purple, with insipid purple flesh. U. S. and Mex. — 

 This species, \\-ith its numerous varieties, is the most 

 ■widelv distributed and abundant of the large, fla,t- 

 stemmed opuntias in the U. S. It varies greatly in dif- 

 ferent localities, and its many forms have not as yet 

 been adequately defined. 



19. phaeacantha, Engelm. A diffuse, semi-prostrate 

 plant, 1-2 ft. high, and freely rooting from lower rnar- 

 gin of joints: joints broadly obovate, moderately thick, 

 4-6 in. long: areoles about 1 in. apart, with short wool 

 and reddish or brownish bristles; spines mostly toward 

 margin or on apex of joints, 2-5, straight and stiff, 

 reddish brown to almost black with lighter tips, 1-2J';2 

 in. long: fls. 2H in. broad, yellow: fr. usually long- 

 p'NTiform, 1 in. or less diam. and twice as long, purple, 

 w-ith greenish acid pulp. .S. W. U. S. and Mex. Var. 

 mkjor, Hort., is a good form. — ThLs species and a 

 number of the following become deep purpUsh green 

 during autumn and winter. In the spring they_ lose 

 their purplish color to a large extent and take it on 

 again in the fall. The spines are also much darker in 

 winter than in summer. 



20. Camanchica, Engelm. & Bigel. A prostrate, 

 widely spreading plant 1-2 J^ ft. high, and freely root- 

 ing at the lower margin of the joints: joints broadly 

 obovate to orbicular, 4-6 in. long, moderately thick: 

 areoles about 1 in. ajjart, with light V)rown short wool 

 and yellowi.sh brown bristles, mostly armed; spines 

 very variable, usually 1-3, sometimes 3-6, on marginal 

 areole.s, reddish to blackish brown with lighter tips, 

 variable in length, sometimes 2}^ in. long: fls. 2J^3 in. 

 wide, yellow, with reddi.sh center: fr. oval to globose, 

 eometimes pyriform, deep red, sweet, edible^ 1-1 /i in. 

 diam. S. \V. U. S. Var. gigantea, Hort., of the trade 

 proves to h<: O. phiKOcantlia. 



21. macrocentra, Engelm. A semi-prostrate, spread- 

 ing plant, 2-3 ft. high: joints strikingly purple-green, 

 ver}' thin, broa'lly obovate to nearly orbicfilar, .5-9 in. 

 diam., with a few remarkably long spines on the mar- 

 ginal areoles: areoles about 1 in. ajiart, grayish wool 

 and .short gravLsh yellow bristles; spines rar(;ly wanting, 

 usually 1-2, reddish brown t^j almost black, annulate, 

 S-5 in. long, slender and straight or variously twisted, 

 eumetimes 1-3 much smaller, lighter colored, secondary 



OPUNTIA 



spines: fls. 3 in. wide, yellow: fr. oval to globose, rarely 

 ovate, 1 in. diam., red; jiulp sweet, edible. S. W. U. S., 

 Mex.— This species is remarkable for its exceedingly 

 long, dark spines and purple joints. 



22. nigricans, Haw. .\ large, robust, upright plant, 

 2-5 ft. high: joints usually obovate, dark green, rai-ely 

 tinged with purple, about 10 in. long and 6 in. wide, 

 modcratelv thick: areoles with short, grayish wool and 

 yellowish 'brown bristles; spines 1-2, awl-shaped, 1-2 

 in. long, strong, dark brown, at first yellowish: fls. 

 11-2-2 in. wide, .yellow with red center. Mex. — Fre- 

 quent in cult. 



23. filipendula, Engelm. A small, semi-prostrate 

 plant, freely branching from the base of the joints, rarely 

 10 in. high" and with thick, tuberous, moniliform roots: 

 joints small and thin, bluish, glaucous, rarely 3 in. 

 greatest diam., orbicular to broadly obovate, sometimes 

 diamond-shaped, frequently flattened at the top and 

 broader than long : areoles orbicular and with an abun- 

 dance of whitish wool and many long, slender, yellowish 

 green bristles, which are very conspicuous, particularly 

 on the older joints; spines sometimes wanting, when 

 present usually 1-3, rarelv more, white, very slender 

 and flexible, 1-2 in. long, mostly margmal: fls. yellow^ 

 l}.)-2 in. diam.: fr. clavate to narrowly obovate, V/2 

 in." long and half a.s wide, greenish yellow, with iexv 

 seeds. Texas to Ariz., extending into Mex. • 



24. himiifasa, Raf. (O. Rafinesquii, Engelm. 0. 

 mesacdntha, Raf.). Fig. 2602 (adapted from Pacific R. 

 R. Report). A wide-spreading, prostrate plant, freely 

 rooting from the lower margin of the joints, roots some- 

 tunes tuberous: joints obovate to orbicular, usually 

 2-5 in. long and 2-4 in. wide, sometimes twice as large, 

 dark to light green: areoles with gray wool and bright 

 reddish brown bristles; spines sometimes wanting, when 

 present 1-3 and mostly marginal, stout, 1 in. long, 

 white with darker tips and bases, frequently 1-3 small 

 secondary spines also present: fls. 3 in. or less diam., 

 golden yellow, frequently with reddish center: fr. 

 slender-clavate or broader, 1^-2 in. long, yellowish red 



2602. Opuntia humifusa. 



