451 
87. Opuntia whipplei spinosior Engelm. Syn. Cact. 307 (1856). 
Taller (small trees 18 to 30 dm. high), with rhombic tubercles, mostly 
longer (12 to 18 mm.), much more numerous (commonly 12 to 14) stellate- 
porrect and mostly radiant spines, cup-shaped flowers 3 to 5.5 cm, 
broad, and larger seeds (4mm.). (Jil. Pacif. R. Rep. iv, t. 17, f. 1-4)— 
Type, Schott 5 of 1855 in Herb. Mo. Bot. Gard. 
Southern Arizona. 
Specimens examined: ARIZONA (Schott 5 of 1855; Pringle of 1881; 
Vasey of 1881; Towmey of 1892, Phoenix and Tucson; Wilcox of 1894, 
Ft. Huachuca). 
In giving the range Schott notes “from Gila River south to Santa Cruz River and 
Tucson and further east.” The flowers are sometimes more or less yellow-tinged,. 
88. Opuntia arborescens Engelm, Wisliz. Rep. 6 (1848). 
Cactus cylindricus James, Cat. 182 (1825); not Cereus cylindricus Haw. Syn. 183 
(1812). 
Cactus bleo Torr. Ann. N. Y. Lye. ii, 202 (1828), not HBK. 
Opuntia exurviato-stellata Lem.; Lab, Monogr, Cact. 492 (1845); but this is only 
Opuntia stellata Salm, ined. 
Arborescent and erect, northward 15 dm. high, southward becoming 
60 to 90 dm. high, 12.5 to 25 em, in diameter, with verticillate, hori- 
zontally divaricate or pendulous very spiny branches: joints verticillate 
(mostly in 3s or 4s), eylindrical and very green, 5 to 15 em, long, less 
than 2.5m. in diameter, with prominent clongated compressed-cristate 
tubercles 14 to 18 mm. long, and terete elongated spreading leaves 12 to 
20 mm. long: pulvini with short wool, but scarcely bristly: spines 5 to 
30, terete, horny or reddish-brown, in straw-colored sheaths, porrect in 
every direction, 1 to 8 interior ones longer (16 to 28 mm.), more loosely 
sheathed, the central subdeflexed, the exterior ones weaker, closely 
sheathed, 8 to 16 mm. long, all sometimes very short: flower purple, 6 
to 7.5 em, broad: fruit globose or hemispherical, 2.5 cm. in diameter, 
variously umbilicate (dependent on prominence of upper tubercles), 
prominently cristate-tuberculate, unarmed, dry or nearly so, yellow; 
seeds regular, smooth, 3 to 4 mm. broad, with narrow commissure. 
(il. Pacif. R. Rep. iv, t. 17, f. 5, 6; t. 18, f 45 t. 24, f, 12; Cact. Mex. 
Bound. t. 75, £. 16, 17)—Type, Wislizenus of 1846 and Fendler of 1847 
in Herb. Mo. Bot. Gard. 
From central Colorado southward through Texas, New Mexico, and 
Arizona into Chihuahua and Sonora and far southward. 
Specimens examined: CoLORADO (Parry, Canyon City; Pringle of 
1881, Trinidad; Alice Eastirood of 1890, Durango; Mrs. S. B. Walker 
of 1894, Canyon City): TEXAS (Wright of 1851-52; G. R. Vasey of 1881, 
El Paso; Evans of 1891): New Mexico ( Wislizenus 307 of 1846; Fend- 
ler 277 of 1847, Santa Fe; Wright 354, 390, 399; Bigelow of 1853-54; 
Bolander of 1872; G. R. Vasey of 1881, Socorro; Mrs, Sumner 1002; 
Carleton of 1891; Evans of 1891, Lordsburg; Mearns of 1892, Carriz- 
allilo Mts.): ARIZONA (Emory of 1848; Coues & Palmer of 1865; Bis- 
