140 
THE CACTACEAE. 
The plant illustrated in Bliihende Kakteen as cited below has flowers of different color 
and shape, and hence is referred here with some doubt. 
Schumann (Gesamtb. Kakteen 349. 1898), following Tabouret, refers as a synonym 
of this species E. campylacanthus Scheidweiler (Allg. Gartenz. 8: 337. 1840), which is 
described as having 21 ribs and only one central spine. It should probably be referred 
elsewhere. The specimens distributed by de Taet under this name seem to be Echinopsis 
leucantha. 
Illustrations: Nov. Act. Nat. Cur. 16: pi. 26; Bliihende Kakteen 3: pi. 134; Schelle, 
Handb. Kakteenk. 162. f. 92; Gard. Chron. III. so: 135. f. 64, E, as Echinocactus macro¬ 
discus; Monatsschr. Kakteenk. 24: 151, as Echinocactus macrodiscus multiflorus. 
Figure 147 is copied from the first illustration above cited. 
Fig. 147.—Ferocactus macrodiscus. 
23. Ferocactus viridescens (Torrey and Gray). 
Echinocactus viridescens Torrey and Gray, FI. N. Amer. i: 554. 1840. 
Melocactus viridescens Nuttall in Teschemacher, Bost. Journ. Nat. Hist. 5 : 293. 1845. 
Echinocactus limitus Engelmann in Coulter, Contr, U. S. Nat. Herb. 3: 374. 1896. 
At first nearly globose or somewhat depressed, in age becoming cylindric, 3 to 4.5 dm. high, 
2.5 to 3.5 dm. in diameter, simple or cespitose, deep green, somewhat glossy; ribs 13 to 21, somewhat 
rounded, 1 to 2 cm. high, obtuse, undulate; areoles narrow, elliptic, 1 to 2 cm. long, spine-bearing in 
the lower part, felted in upper part, flower-bearing and also with several reddish glands, these 
becoming elongated and spinescent in age; spines at first bright red, becoming duller by age or turn¬ 
ing yellow or horn-colored; radial spines 9 to 20, more or less spreading, 1 to 2 cm. long; central 
spines 4, the lower one stouter and more flattened, up to 3.5 cm. long; flowers yellowish green, 4 cm. 
long; perianth-segments oblong, obtuse, sometimes apiculate, more or less serrulate on the margins; 
flower-tube bearing stamens almost to the top of the ovary; scales on the ovary orbicular, imbricate; 
fruit 1.6 to 2 cm. long, reddish with a pleasant acid taste; seeds 1.6 mm. long, pitted. 
Type locality: Near San Diego, California. 
Distribution: California and Tower California near the International Boundary Tine, 
not far from the sea coast and in the foothills. 
Echinocactus viridescens is usually credited to Nuttall, but he referred it in manuscript 
to Melocactus, and Torrey and Gray, who revised and published his manuscript, referred 
it doubtfully to Echinocactus. 
