1148 



OPUNTIA 



crowded, with fine, gray wool and very numerous golden 

 yellow bristles of unequal length ; spines 3-6, rarely 

 none, on old stems occasionally 40 or more, unequal, 

 angular, golden yellow, deflexed, usually 1 in. or less 

 long: fls. yellow, 2-3 in. in diam: fr. deep purple, moder- 



U'loh 



1546. Hedge of Opuntia Tuna. 



tlv. edihle, IV2 in in diam., broadly obovate to 

 serds comparatively small, sometimes sterile. 



IT. pycnacantha, Engelm. An upright, moderately 

 br:iii.li.il plaint, il-.l ft. high: joints oval to orbicular, 

 oi-i;i~.j,,M;illy somewhat pointed at the ends, 4-8 in. 

 long, sometimes pubescent, armed with a densely inter- 

 woven covering of mostly dellexed spines : areol» 

 crowded, approximately Kin. apart, with dark brown 

 wool and numerous long, yellow bristles; spines 3-7, on 

 old stems 20 or more, straw-colored to ashy, mostly less 

 than 1 in. long: Us. greenish yellow, 2-3 in. broad: fr. 

 obovate, 114 in. in diam. and covered with numerous 

 spines and bristles. Lower Calif. 



18. £ngelmaiinii, Salm. Pig. 1547. An erect to semi- 

 prostiale. profusely branching, coarse plant. 'J-r. ft. 

 hi;;li. forming large, impenetrable thickets, usually 

 with a short, more or less terete, woody trunk, with 

 grayish bark which becomes unarmed with age: joints 

 broadly obovate to orbicular, pale to bluish green, very 

 variable in size, in large specimens 12-14 in. long ami 

 nearly as wide, moderately thick : areolaa remote, about 

 1 in. apart, with gray wool and large, rigid, gray to yel- 

 low, unequal bristles; spines mostly 2-t, sometimes 1-3 

 small additional ones, very variable, homy, variously 

 colored, mostly yellow, or white with reddish base. 

 usually compressed or angular and curved or twisted ; 

 Hs. yellow, red within, fading lo n cl. -",-:! in, in diam. : 

 fr. broadly pyriform to gIol»iv. , tn .|ii. ntly 2 in. in 

 diam., dark purple, with in^iin.l imrplr tlrsh. U. S. 

 and Mex.— This species, with its nuim muv varieties, is 

 the most widely distributed and abiinaaiit of the large, 

 flat-stemmed Opuntias in the United States. It varies 

 greatly in different 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 mar- 

 gin of joints: joints broadly obovate, moderately thick. 

 4-6 in. long : areolte 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, 1-2K 

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

 pyriform, 1 in. or less in diam. and twice as long, pur- 

 ple, with greenish acid pulp. Southwest U. S. and 

 Mex. — This species and a number of the following be- 

 come deep purplish green during autumn and winter. 

 In the spring they lose their purplish color to a large 



extent and take 



also much dark 



20. Caminchi 



widely spreadin 



OPUNTIA 



I again in the fall. The siJiues are 

 wiiiti-r than in suuuuer. 

 iiL'i iin. :iiid Begel. A prostrate, 

 It I-_" . It. high, and freely rooting 

 I III. |. II Ills: joints broadly obovate 



iiL' til aiflv thick: areolEP about 



I li' n .• .,..1 and yellowish 



! r:i,.^ very variable. 



'!■ 11 . I -I'lil areola?, reddish 

 ' ! h^i ii iiiji-. \ a liable in length, 

 - : ii~. L".-:; in. wide, yellow, with 

 ..val to globose, sometimes pyri- 

 I. iilitii''. 1-lK in. in diam. South- 

 \ ai. gigantea of the trade proves to be 



O. pluKn.u.tl,., 



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

 plant. "J-l! ft. hii^h : joints strikingly purple-green, very 

 thin, broailly ohc. vat. to nearly orbicular, 5-9 in. in diam.. 



olie: areolce alimit 1 in. apart, with riayi^h wool and 

 short, grayish y.-llow- hn-il-'^; ~|'iii' > tartl> wanting, 

 usually 1-2, n-.i'li-li l.n.Hii t.. :iliiii.-t l.laik, animlate 

 3-5 in. long, slciidi-r ami siraiglit or vaiioiisly twisted, 

 sometimes 1-3 much sitialler, lighter colored, secondary 

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

 rarely ovate, I In. in diam., red ; pulp sweet, edible. 

 Southwestern U. S., Mex. — This .species is remarkable 

 for its cxi-eeiliiiL'ly I..11-. .lark spines and purple joints. 



22. nigricans, 

 -5 ft. hii;li: .1.11 



robust, upright plant, 

 ■ate, dark green, rarely 

 I. long and i\ in. wide, 



-iMiit, L-i ;i\ i-li «..ol and 



cquent 



tinged with i.iii|il. :iIm,,,i 



moderately tin. : ,1 



yellowish bro" i 



in. long. str.iiiL ■! 1 1 ' 



lK-2 in. wid... >.i: M 



in cultivation. 



23. filipSndula, Engelm. A small, semi-prostrate plant, 

 freely Inanching from the base of the joints, rarely 10 

 in. hisrh and with thick, tuberous, moniliforni roots: 

 joints ,,ii;ill Till. I itiiii, bluish, glaucous, rarely 3 in. in 



great. 1 '111 i. I liar to broadly obovate, sometimes 



diaii '■ III. ntly Hattened at the top and 



broa.l. : _ .li.la. orbicular and with an abun- 



danc'-' "1 ^^ Inn li \^.H■[ and many long, slender, yellowish 

 green bristles, which arc very conspicuous, particularly 

 on the older joints; spines sometimes wanting, when 

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

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



1547. Opi 



Engelmannii (> 



l^^-2 in. in diam.: fr. clavate to narrowly obovate, V/i 

 in. long and half as wide, greenish yellow, with few 

 seeds. Texas to Ariz., extending into Mexico. 



24. BafinSsqnii, Engelm. (O. me.«aca'?i/;i«, Kafin.). A 

 wide-spreading, prostrate plant, freely rooting from the 

 lower margin of the joints, roots sometimes tuberous: 

 joints obovate to orbicular, usually 2-5 in. long and 2-4 



