814 OPUNTIACEAE 
Stems erect: branches equally 3-8-angled. 
Branches 6-8-angled. 1. C. monoclonos. 
Branches 3-4-angled. ? 2. C. princeps. 
Stems reclining or procumbent: branches climbing, unequally 3-5-sided. 
Central spine minute: radial spines conic: plants with aérial roots. 3. C. triangularis. 
Central spine 1-2 em. long: radial spines subulate: plants without aérial roots. 4. C. Bazaniensis. 
1l. Cereus monoclónos DC. Stems columnar, 1-3 m. tall, erect, green, the ribs 6-8, 
obtuse: spines brownish, radiant, varying from very short to 3.5 cm. in length: flowers 
mainly white, 15 cm. long: fruit about 5 cm. long. 
In sand, peninsular Florida and the West Indies. 
2. Cereus prínceps Pfeif. Stems erect, 1-3 m. tall, 5 cm. thick, 3-4-angled : areolae 
distant: spines unequal; outer radiant, 4—6, stout, often 2.5—3.5 mm. long ; central de- 
flexed : flowers white, 17-20 cm. long, 13-15 em. broad : fruit oval, 5-7.5 cm. long, spiny, 
scarlet without, red and pulpy within: seeds 3-3.5 mm. long, smooth and shining. 
Along the lower Rio Grande on the Mexican side and probably on the Texas side. WUERZLE. 
3. Cereus triangularis (L.) Haw. Stems reclining or procumbent, elongated, 
branched, the branches often rooting at the joints, 3-angled or with a flat side and 2 grooved 
sides, the joints commonly 32 em. long, 5-7.5 cm. broad, occasionally twisted, the ribs at 
first wing-like, with remote areolae : spines 3—5, rigid, blackish, somewhat recurved, 2-4 
mm. long, upper ones shorter than the lower : flowers white, 20 cm. broad : fruit commonly 
10 em. long, scarlet, smooth. 
In sand, peninsular Florida, the West Indies and Central America. 
4. Cereus Baxaniénsis Karw. Similar to C. triangularis in habit, but lacking the 
aérial roots. Stems sometimes 8 m. long, the joints various, a 3-angled one often arising 
from a 5-angled one: spines 5-8, the radial bristle-like or subulate, brittle, the central 
one 1-2 cm. long: flowers and fruit unknown. 
In sandy soil or coral rock, Florida Keys and the coasts of the West Indies and tropical America 
4. ECHINOCACTUS Link & Otto. 
Fleshy plants, with globular oblong or cylindric stems, with spine-bearing ribs or 
vertical or spiral rows of tubercles. Leaves obsolete, flowers arising from areolae on the 
tubercles near the areolae which later produce spines. Hypanthium with naked scales 
or others bearing wool in their axils, prolonged beyond the ovary. Petals numerous, 
merging into the sepals. Ovary 1-celled: stylecolumnar. Stigmas slender, numerous. Berry 
fleshy or dry, with scales, or tufts of bristles. Seeds often with endosperm. Embryo curved. 
Spines, especially the central, very slender, terete. P 
Ribs less than 10: central spines 4. 1. E. Schottit. 
Ribs more than 12: central spines 1-3. i 2. E. setispinus. 
Spines, erpecialiy the central, stout, flattened. , 
Central spines straight or slightly curved. 3. E. Texensis. 
Central spines hooked. 
Radial spines mostly 8: central spines 5-15 em. long: flowers 2.5-3.5em. long. 4. E. Wrightii —.... 
Radial spines 10-12: central spines 25-35 mm. long : flowers 5-7 cm. long. 5. E. Muhlenpfordtit. 
1. Echinocactus Schéttii ( Engelm.) Small. Stems ovoid or cylindric-ovoid, 10-15 
em. high, 5-7.5 em. thick, usually solitary, the ribs often 8, oblique: spines all or some 
variegated with red and white ; outer 15-17 radiant, straight, variable in length ; cent 
usually 4, of 2 kinds; uppermost 3-4 cm. long, flat above, keeled beneath, straight ri 
slightly curved, the three lower ones much shorter, nearly terete or somewhat flattened, 
straight : flowers mainly purple, 5-7.5 cm. long. [E. bicolor var. Schotti Engelm. ] 
On limestone hills, southern Texas and adjacent Mexico. 
2. Echinocactus setispinus Engelm. Stems subglobose, solitary, 5-9.5 cm. 1n y 
ameter, the ribs 13, somewhat oblique, more or less undulate or even slightly interrupted : 
spines various ; radials 14-16, bristle-like, 1-2 cm. long, the upper longer than the rest pus 
like the lower, yellowish brown, the lateral ones white; centrals 1-3, darker cid A 
radials, 24-32 mm. long, bristle-like: flowers 4-7 cm. long, yellow and scarlet ys "E 
fruit subglobose, about 8 mm. in diameter, red: seeds obliquely globose-ovoid, 1.2-4. 
mm. long, tuberculate. : 
In mesquite thickets and dry soil, from the valley of the Brazos, Texas, south ward into Mexico. 
3. Echinocactus Texénsis Hoepf. Stems depressed or rarely subglobose, 2-3 2€: 
broad, seldom over 15 cm. high, solitary, simple, the ribs 13-27, usually 21, wavy : T o0 
reddish, stout, flattened, clustered ; radials 6-7, straight or slightly curved, spr eading, m 
mm. long, rarely longer or shorter; centralone surpassing the outer, commonly ye v: io 
broad or slightly broader, straight or slightly curved : flowers orange and scarlet benn 
