246 CACTACE^E. Echinocactus. 



Arizona and Sonora to the Mohave region {Emory, Biyelow, Kchott), and into Lower California, 

 Gabb. Plants 1 or 2 and even 3 feet high, 1 or 2 feet thick ; all the spines very stout and 

 strongly cross ribbed, 1^ to 3 inches long ; flowers 3 inches long, purplish brown outside ; petals 

 red, with yellow margin ; seeds much like those of the next species. 



6. E. Wislizeni, Engelm. Very large, oval, at last cylindrical or often club- 

 shaped, with 21 to 30 compressed crenate ribs : oblong areolte bearing various 

 spines ; in the centre 4 stout cross-ribbed ones, the lower one flattened and curved 

 or hooked; above and below 6 to 10 slightly ribbed, and laterally 10 to 20 

 long slender often flexuous ones : flowers greenish yellow, 2 to 2^ inches long : 

 ovary and fruit imbricately covered with 30 or 40 to 60 or 100 roundish cordate 

 sepals ; inner sepals spatulate, 20 to 30 : petals as many, lanceolate, crenulate : style 

 divided to the middle into 12 to 20 stigmas : yellowish berry at last hard and dry ; 

 seeds over a line long, reticulated. Wislizenus Rep. 1848, note 14; Cact. Mex. 

 Bound. 23, t. 25, 26. 



From the Rio Grande to the Colorado, northward into Utah and west into California ; flower- 

 ing throughout the summer and autumn. Often 3 and even 4 feet high and 1 or 2 in diameter, 

 with a woolly spineless top ; spines 1 to 2^ inches long, grayish red, the thinner ones whitish. 

 E. Lecontei, Engelm., seems to have been founded on weaker plants of this, with the seeds of per- 

 haps No. 4. 



* * Scales of the ovary subulate, often spinescent, copiously woolly in their axils ; fruit 

 enveloped in ivool. Eriocarpi. 



7. E. polycephalus, Engelm. & Big. Middle-sized or large, globose, at last 

 cylindric, sprouting from the base ; ribs 13 to 21, acute : circular areolse bearing 8 to 

 1 2 stout compressed annulated curved reddish gray spines : flowers enveloped in a 

 mass of dense white wool: petals about 30, lance-linear, yellow : stigmas 8 to 11, 

 linear: dry berry full of large angular seeds. Cact. of Pacif. R. Rep. iv. 31, t. 3, 

 fig. 4-6. 



Gravelly or stony soil on the Colorado and Mohave rivers, and in the Californian desert (Bigc- 

 Imv) ; flowering in February, fruiting in March. Heads sometimes 20 or 30 from a single base, 

 \ to 1^ feet high, the larger cylindric ones 2 to 2 feet high ; spines either all radial, or 6 to 8 

 outer ones surrounding 4 stouter central ones ; flowers 1^ inches long ; about 100 rigid dark pointed 

 sepals upon the ovary are hidden in the wool, those of the tube similar and about as many ; petals 

 about 30, narrow, yellow, just emerging from the wool ; seeds 2 lines long, wrinkled and minutely 

 tuberculate. 



3. CERETJS, Haworth. 



Flowers about as long as wide or elongated. Scales of the ovary distinct, with 

 naked or woolly axils, or almost obsolete and the axils spiny. Berry succulent, 

 covered with spines or scales or almost naked. Seeds black, without albumen. 

 Embryo short and straight or curved or hooked ; cotyledons usually contrary to the 

 sides of the seed. Plants of all sizes, low or climbing or erect, sometimes enor- 

 mous ; spine-bearing areolse on vertical ribs. Flowers from the older or, at least, 

 fully formed parts of the plant, not from any preformed areola, but bursting through 

 the epidermis just above the bunches of spines ; some open only in sunlight, others 

 only at night, others again are not thus influenced. Fruit often edible, sometimes 

 of very large size. 



1. Low and usually cespitose plants, mostly with numerous oval or cylindric heads, 

 short flowers, green stigmas, and spiny fruit : seeds subglobose, covered with con- 

 fluent tubercles : embryo straight, with very short cotyledons. ECHIXOCEREUS. 



1. C. Engelmanni, Parry. Heads several from a single base, oval or cylin- 

 drical, with 11 to 13 interrupted ribs : radial spines about 13, whitish, often some- 

 what angled, straight or curved, the lateral ones the longest ; central ones 4, longer, 



