2. Opuntia Humifúsa Raf. Western Prickly Pear. Devil's Tongue

Fig. 2987

Cactus humifusus Raf. Ann. Nat. 15. 1820. Opuntia humifusa Raf. Med. Bot. 2: 247. 1830. O. mesacantha Raf.; Ser. Bull. Bot. Gen. 216. 1830. O. Rafinesquii Engelm. Pac. R. R. Rep. 4: 41 1856.

Prostrate, similar to the preceding specie;;; joints obovate to suborbicular, or oval, usually deep green, 2'-5' long; leaves subulate, spreading, 3'-5" long; bristles reddish brown; spines few, mostly near the margins of the joints, 1-4 together, whitish, or reddish at base and apex, deflexed, or the longer one spreading and 1/2-l long; flowers yellow, often with a reddish centre, 2 1/2'-3 1/2' broad; petals 10-12; fruit club-shaped, not spiny, fleshy, edible, 1 1/2-2' long.

In dry sandy or rocky soil, Ohio to Minnesota, Kentucky, Missouri, Nebraska and Texas. Summer.

Opuntia macrorhiza Engelm., a related species with a deep woody root, abundant in Texas, is reported to range northward into Missouri and Kansas.

2 Opuntia Humif Sa Raf Western Prickly Pear Devil  1329

3. Opuntia Tortispina Engelm. Twisted-Spined Cactus

Fig. 2088

Opuntia tortispina Engelm. Pac. R. R. Rep.

4: 31. 1856.

Stems prostrate, the orbicular-obovate flattened joints 6-8' long. Spines 3-5, yellowish, becoming whitish, angled and channeled, sometimes twisted, the longer ones 1 1/2'-2 1/2' long, with 2-4 more slender and shorter ones; flowers sulphur-yellow, 2V-3' broad; fruit ovoid, fleshy, unarmed, about 2' long and 1' in diameter; seeds orbicular, slightly notched at the hilum, 2"-3" wide.

Plains of Missouri and Nebraska to Texas. Summer.

3 Opuntia Tortispina Engelm Twisted Spined Cactus 13303 Opuntia Tortispina Engelm Twisted Spined Cactus 1331

4. Opuntia Camànchica Engelm. Comanche Cactus

Fig. 2989

Opuntia camanchica Engelm. Pac. R. R. Rep. 4: 40. 1856.

Prostrate, with obovate-orbicular flattened joints 6'-8' long, 5'-8' wide. Spines 1-3, flattened, reddish brown to blackish, 1 1/2-3' long, or with 3-6 additional shorter ones, the upper one suberect, the others deflexed or spreading; flowers yellow, about 2 1/2' broad; fruit oval, deep red, juicy, 1 1/2-2' long; seeds angular, margined, deeply notched at the hilum, 2"-3" broad.

Western Kansas (according to B. B. Smyth); Colorado to Texas and Arizona.

The plant of western Kansas differs from the typical Texan one by having more slender spines, lighter in color. It hybridizes with O. fragilis.

4. Opuntia Polyacàntha Haw. Many-Spined Opuntia. Tuna

Fig. 2990

Cactus ferox Nutt. Gen. 1: 296. 1818. Not Willd. 1813.

Opuntia polyacantha Haw. Syn. Pl. Succ. Suppl. 82. 1819.

Opuntia missounensis DO Prodr. 3: 472. 1828.

Prostrate, joints broadly obovate to orbicular, tubercled, pale gree: , 2'-6' long, about 6" thick, the tubercles 2' high, densely spiny and with cushions of fine bristles; spines 5-12, slender, 6"-2' long, whitish; leaves minute; flowers light yellow, 2-3' broad; fruit dry, very prickly, 1'- 1 1/24' long.

Plains and dry soil, Wisconsin to South Dakota, Athabasca, British Columbia, Nebraska, Missouri, Utah and New Mexico. May-June.

4 Opuntia Polyac Ntha Haw Many Spined Opuntia Tuna 13324 Opuntia Polyac Ntha Haw Many Spined Opuntia Tuna 1333