427 
25. Opuntia camanchica Engelm. Syn. Cact. 291 (1856). 
Prostrate and extensively spreading, with ascending obovate-orbicular 
joints 15 to 17.5 em. long by 13.5 to 17.5 em. broad: pulvini about 3 em, 
apart, with few greenish or yellowish-brown bristles, mostly armed: 
spines 1 to 3 (or marginal ones 3 to 6), compressed, reddish-brown to 
blackish-brown, paler at tip, 3.5 to 7.5 cm. long, the upper one elongated 
and suberect, the rest deflexed: fruit oval, with broad umbilicus, deep 
red, sweet and juicy, 3.5 to 5 cm. long: seeds angular, with broad thick 
acute or obtuse nargins and deeply notched at the hilum, 4 to 6 mm. 
broad. (11. Pacif. R. Rep. iv, t. 9, f. 1-5; t. 22, f. 12-15)—Type, Bigelow 
of 1853 in Herb. Mo. Bot. Gard. 
In rather fertile soil ‘‘at base of hills,” from southern Colorado 
through western Texas, New Mexico, and Arizona. 
Specimens examined: CoLoRADO (Engelmann of 1881): TEXAS 
(Evans of 1891, near EK] Paso): NEw MExico (Bigelow of 1853): 
ARIZONA (Palmer of 1869; Hvans of 1891; Trelease of 1892). 
This species is reported from the Llano Estacado, on the Upper Canadian, as a 
large and extensively spreading plant. 
26. Opuntia tortispina Engelm. Syn. Cact. 293 (1856). 
Prostrate, with ascending orbicular-obovate joints 15 to 20 em. long: 
pulvini 2.5 to 3.5 em, apart, with yellowish bristles: spines 5 to 5, 
white, angular, and channelled, often spirally twisted, 3.5 to 6 cm. long, 
with 2 to 4 more slender ones (1 to 2.5 em. long) added below: tlowers 
sulphur-yellow, 6 to 7.5 cm. broad: fruit ovate, with broad umbilicus, 
4.5 to 5 em. long: seeds orbicular, regular, and but Slightly notched at 
hilum, 4 to 6 mm. broad. (Zi. Pacif. R. Rep. t. 8, f. 2,35 t. 23, f. 1-5)— 
Type, Bigelow of 1853 in Herb. Mo. Bot. Gard. 
From the plains of the Platte, Nebraska, to those of Indian Territory 
and northern Texas. 
Specimens examined: NEBRASKA (41. Engelmann of 1858): INDIAN 
TERRITORY (Bigelow of 1853). 
27. Opuntia mojavensis Engelm. Syn. Cact. 393 (1856). 
Prostrate, with suborbicular joints: pulvini remote, with large yellow 
bristles: spines 2 to 6, stout and annulate, acutely angular and com- 
pressed, more or less curved, reddish-brown, paler toward tip, 2.5 to 6 
em, long, 1 to 3 smaller slenderer pale ones added below: fruit oblong, 
4.5 cm. long. (Jil. Pacif. R. Rep. t. 9, f. 6-8)—Type, Bigelow of 1853 
in Herb. Mo. Bot. Gard. 
“On the Mohave, west of the Colorado,” California. 
Specimens examined: CALIFORNIA (Bigelow of 1853). 
(3) Ascending : joints rather small: spines few, terete or scarcely angular, slender, 
flexible, pale: fruit smaller than in (2). 
28. Opuntia tenuispina Engelm. Syn. Cact. 294 (1856). 
Diffuse or ascending, about 3 dm. high, with obovate bright-green 
joints attenuate at base and 7.5 to 15cm. long by 5 to 10 cm. broad: pul- 
28 
