433 
43. Opuntia pes-corvi Le Conte; Chapm. Fl, 145 (1860). 
Prostrate and diffuse, bright-green, with small ovate or obovate swol- 
len and often teretish fragile joints 2.5 to 7.5 em. long and half as thick: 
pulvini 8 to 16 mm. apart, with few very short slender and pale bristles, 
the lowest unarmed: spines 1 to 3, straight and slender, rigid, often 
compressed at base and twisted, dusky, 2.5 to 3.5 em, long: flowers 
yellow, 3.5 to 4.cm. broad: fruit obovate, bristly, rose-purple, with shal- 
low umbilicus, tleshy, 12 to 14 mm. long: seeds very few (1 or 2), nar- 
rowly and obtusely margined, 4 mm, broad.—Type unknown. 
Barren sands, coast of Georgia and Florida. 
Specimens examined: FLORIDA (Chapman of 1856 and 1860; JZiteh- 
cock of 1890): also cult.in Harv. Bot. Gard., 1871; Mo, Bot. Gard., 1582. 
Evidently very near O. opuntia, and possibly only a small thick-jointed variety. 
a+ ++ Joints pubescent: erect or procumbent. 
(1) Flowers yellow: spineless plants. 
44, Opuntia microdasys Lehm. Ind. Sem. Hamb. 16 (1827). 
Opuntia pulvinata DC, Rev. Cact, 119 (1828). 
Erect-spreading, 6 to 12 dm. high: joints oblong-obovate or orbicular, 
pubescent, bright-green, 5 to 7.5 em. long by 3.0 to 5 em. wide: leaves 
minute: pulvini 12 to 16 mm. apart, with yellow wool and numerous 
very slender yellow bristles, spineless: flowers yellow: fruit unknown.— 
Type unknown. 
From Coahuila to southern Mexico. 
Specimens examined: COAHUILA (Gregg 254 of 1847; Palmer of 1880; 
Pringle 3592): also growing in Mo. Bot. Gard., 1893. 
45. Opuntia rufida Engelm. Syn. Cact. 298 (1856). 
Erect-spreading, 6 to 12 dm. high, much branched: joints broadly 
obovate or suborbicular, pubescent, pale-green, 5 to 15 cm. long: leaves 
long acuminate, 5 mm. long: pulvini crowded, with penicillate tufts of 
very numerous slender reddish-brown bristles, spineless: flowers yel- 
low, 6 cm. broad.—Type, Bigelow and Gregg specimens in Herb, Mo. 
Bot. Gard. 
On the Rio Grande (on rocks and mountains) about Presidio del 
Norte, Chihuahua, southward to the valley of the Nazas, Durango. 
Specimens examined: CHIHUAHUA (Bigelow of 1852, about Presidio 
del Norte): DURANGO (@regg 634, valley of the Nazas). 
Differs from O, microdasys in its more rounded and larger joints, longer leaves, and 
reddish-brown bristles. 
(2) Flowers red. 
46. Opuntia basilaris !ingelm. Syn. Cact. 298 (1856), 
Low, with obovate or triangular glaucescent minutely pubescent 
ascending joints 12.5 to 20 em, long and proliferous (almost rosulate) 
from the base: leaves minute, 2mm. long: pulvini 8 to 12 mm. apart, 
