373 
38. Echinocactus bicolor Gal.; Pfeiff. Abbild. Cact. ii, t. 25 (1843-50), 
Echinocactus bicolor pottsii Salm, Cact, Hort, Dyek. 173 (1850). 
Echinocactus pottsii Scheer; Seem. Bot. Herald, 291 (1852-57), not Salm. 
Globose-ovate, stout, 3.5 to 10 cm. in diameter, sometimes becoming 
2G cm. high: ribs 8, oblique and obtuse, compressed: lower radial spines 
and centrals variegated red and white; radials 9 to 17, spreading and 
recurved, slender and rather rigid, the lowest one shortest (1.5 to 2 ¢m.), 
the laterals longer (2 to 4 ¢m.), about equaling the 2 to 4 flat flexuous 
ashy upper ones; centrals 4, flat and flexuous, 3 to 6 cm. long, the upper- 
most thin and not longer than the erect and rigid laterals, the lowest 
very stout, porrect and very long: flowers funnelform, purple, 5 to 7.5 
em. long: fruit unknown, = (/1l. 1. ¢.)—Type unknown. 
Chihuahua, Coahuila, and San Luis Potosi. 
Specimens examined: CHULUAHUA ( Wislizenus of 1846; Potts of 1850; 
Hvans of 1891): COANUILA (Palmer 379): SAN Luts Porost (Palmer of 
1879; Hschanzier of 1891): “Northern Mexico” (Poselger): also speci- 
mens cultivated in Mo, Bot. Gard., 1881, and in Harvard Bot. Gard., 
1882. 
The radial spines usually number 9 to 11, but the Chihuahua specimens of Evans 
show 14 to 17, thus resembling schottii. The chief distinctive character between the 
two is found in the relative development of the centrals, in bicolor the lowest, in 
schottti the uppermost being the most prominent. In the former, also, the uppermost 
central is not only not more prominent than the laterals, but it is flat; while in the 
latter it is not only the most prominent but is carinate below. 
fod 
39. Bchinocactus bicolor schottii Engelm. Syn. Cact. 277 (1856). 
Ovate or ovate-cylindric, 10 to 15 em. high, 5 to 7.5 em, in diameter: 
radial spines 15 to 17, straight; uppermost central broadest and longest 
(3 to 4 em.), flat above and keeled below, straight or a little curved, the 
3 others compressed or subterete, shorter and straight.—Type, Schott 
of 1855 in Herb. Mo. Bot. Gard. 
“On cretaceous hills covered with chaparral,” from near Mier on the 
Lower Rio Grande, Texas, to San Luis Potosi, 
Specimens examined: TEXAS (Schott of 1853): SAN Luis Povrost 
(Palmer of 1882). 
40. Echinocactus orcuttii Engelm. West Amer, Sci. ii, 46 (1886). 
Cylindrical, 6 to 10.5 dm. high, 3 dm, in diameter, single or in clus- 
ters up to 18 or more, not rarely decumbent: ribs 18 to 22, often oblique: 
spines extremely variable, angled to flat, 1 to 7 mm. wide; radials 11 
to 15, unequal, lowest and several laterals thinnest; centrals 4: flowers 
about 4 cin, long, deep-crimson in center bordered by light greenish- 
yellow: fruit globose and green, about 16 mm. in diameter: seeds 
(unripe) brown, tuberculate, 1.5mm, long, (27, W. Amer, Sci. ii, 47)— 
Type, Orcutt of 1883 in Herb. Mo. Bot. Gard. 
‘Palm Valley, Lower California, 30 to 50 miles southeast of San 
Diego.” 
Specimens examined: LOWER CALIFORNIA (C. Jt. Orcutt of 1883). 
