CACTUS FAMILY 145 



1. Opuntia ramosissima Engelm, Lead Pencil Cholla. Fig. 3301. 



Opnntia ramosissima Engelm. Amer. Journ. Sci. II. 14: 339. 1852. 



Opuntia tessellata Engelm. Proc. Amer. Acad. 3: 309. 1856. 



Cylindropuntia ramosissima F. M. Knuth in Backeb. & Knuth, Kaktus-ABC 124. 1935. 



Low bush 0.4-2 m. high, with gray-green, widely spreading branches 0.5-1 cm. in diam- 

 eter. Joints 2.5-10 cm. long; tubercles low, crowded, 5-8 mm. long, nearly as wide, 4- or 6- 

 angled, covering the surface with diamond-shaped plates ; leaves ovoid, 1-3 mm. long, acute ; 

 areoles circular when young, compressed into a narrow slit in age, with white to tawny wool and 

 pale yellow glochids ; spines 1-4 at an areole 1 larger if more than 1, often wanting, acicular, 

 porrect to spreading, 1-6 cm. long, reddish when young, nearly white in age, covered by a loose 

 yellow papery sheath ; flowers 3-4 cm. long, including the ovary ; sepals subulate ; petals obovate, 

 9-12 mm. long, aristulate, greenish yellow, tinged with red; stamen-filaments greenish yellow, 

 anthers orange ; style and stigma cream-colored ; ovary narrowly obconic, covered with low 

 emarginate tubercles, areoles filled with wool, glochids and 10-15 unsheathed spines; fruit dry, 

 1-2.5 cm. long, the spines making it appear bur-like; seeds few, lenticular, 3-5 mm. wide, 

 stramineous. 



Low hills and desert flats, Lower Sonoran Zone; from the vicinity of Victorville, San Bernardino County, 

 and western Colorado Desert to southern Nevada, Arizona, and northwestern Sonora. April-May. 



2. Opuntia acanthocarpa Engelm. & Bigelow. Buckthorn Cholla. Fig. 3302. 



opuntia acanthocarpa Engelm. & Bigelow in Engelm. Proc. Amer. Acad. 3: 308. 1856. 

 Cylindropuntia acanthocarpa F. M. Knuth in Backeb. & Knuth, Kaktus-ABC 124. 1935. 



Erect, slender, terminally branched shrub 1-2 m. high. Terminal joints 4-25 cm. long, 2-3.5 

 cm. in diameter; tubercles prominent, 2-2.5 cm. long and laterally flattened; spines SylS, unequal, 

 1.5-3.5 cm. long, yellowish to dark brown, each covered with a light yellow or whitish sheath; 

 glochids numerous, yellow; flowers reddish to brownish yellow, 5 cm. long and wide when 

 expanded ; perianth-segments broadly obovate, obtuse ; ovary short-turbinate, with a few promi- 

 nent tubercles bearing 8-12 rigid acicular spines from middle to apex; fruit dry, 2.5-3.5 cm. 

 long, naked below, tuberculate and spiny above the middle; seeds crowded, irregularly angled, 

 4^6 mm. long, light yellowish. 



Desert mesas and slopes, Lower Sonoran Zone; eastern Mojave and Colorado Deserts, California, to 

 southern Utah, central Arizona, Sonora and northern Lower California. April-May. 



Opuntia acanthocarpa subsp. Ganderi C. B. Wolf, Occ. Papers Rancho Santa Ana Bot. Card. 1 : 75. 

 1938 Plants of vigorous growth; joints brighter green; spines 20-25, more slender, the lower ones deflexed; 

 flowers smaller. San Felipe Valley, San Diego County, and southward along the east base of the Laguna 

 Mountains and desert slopes of San Jacinto Mountains, California. 



3. Opuntia Parryi Engelm. Valley Cholla. Fig. 3303. 



opuntia Parryi Engelm. Amer. Journ. Sci. II. 14: 339. 1852. 



Opuntia bernardina Engelm. in Parish, Bull. Torrey Club 19: 92. 1892. 



Cylindropuntia Parryi F. M. Knuth in Backeb. & Knuth, Kaktus-ABC 124. 1935. 



x\n erect or ascending, openly, sparingly to profusely branched shrub 0.5-1.5 m. high. Joints 

 slender, 7-30 cm. long, 1.5-2 cm. in diameter; tubercles 1.5-2.5 cm. long, narrow, with 1-5 (8) 

 unequal, slender, brownish spines 0.5-3 cm. long at the apex of each, the longest spme usually 

 porrect or deflexed ; glochids brown, fading to yellow or ash-colored ; flowers m clusters of 3-8 

 at the ends of older stems, 2-3 cm. long ; sepals green to reddish ; petals obovate, obtuse, yellow 

 tinged with red ; fertile fruit 2-3 cm. long, ovoid, deeply and broadly umbihcate, more or less 

 tuberculate above the middle, the areoles bearing yellowish glochids, and the upper ones 1-7 

 acicular spines 5-12 mm. long; sterile fruit subglobose to obovoid, fleshy, less spmy; seeds few, 

 whitish, 4-6 mm. broad, the margin shallowly grooved. 



Dry gravelly fans and washes and in interior valleys, Lower and Upper Sonoran Zones; Cuyama Valley, 

 Santa Barbara County, Los Angeles County in the vicinity of San Fernando, to the San Bernardino Valley, 

 and eastern San Diego and western Imperial Counties, California. April-June. 



4 Opuntia echinocarpa Engelm. & Bigelow. Summer Cholla or Staghorn Cholla. 



Fig. 3304. 



opuntia echinocarpa Engelm. & Bigelow in Engelm. Proc. Amer. Acad. 3: 305. 1856. 



Opuntia echinocarpa var. major Engelm. loc. cit. 



Opuntia echinocarpa var. robustior J. M. Coult. Contr. U.S. Nat. Herb. 3: 446. 1896. 



Opuntia dcserta Griff. Monatss. Kakteenk. 23: 132. 1913. 



Cylindropuntia echinocarpa F. M. Knuth in Backeb. & Knuth, Kaktus-ABC 124. 1935. 



Erect, ascending or spreading branched plant 0.5-1.5 m. high. Joiiits turgid, 8-25 cm. long, 

 1.5-2.5 cm. in diameter; tubercles prominent, broadly ovate, about 1 cm. long; areoles /-o, 

 bearing stout spines 2-3 cm. long and 6-12 shorter, more slender ones, fine yellowish wool and 

 glochids; spines interlocking; flowers clustered at end of older branches, 2-3.5 cm. long, yellow 

 tinged with red ; ovary short-turbinate, tuberculate and densely clothed on the upper two-thirds 

 with acicular spines 8-20 mm. long; fruit 1.5-2.5 cm. long, very spiny over upper two-thirds, 

 6-12 spines in each areole ; seeds numerous, 5-6 mm. long, the margins grooved. 



Desert areas and dry interior foothills, Lower and dry ridges in lower Upper Sonoran Zones, Mojave and 



Colorado Deserts and adjacent western foothills to Utah, Sonora, and northern Lower California. April June. 



Opuntia echinocarpa var. Parkeri (Engelm.) J. M. Coult. Contr. U.S. Nat. Herb. 3: 446. 1896. Plant 



