366 
(Gregg 464): CoATIUILA (Palmer 373, 374): NUEVO LEON (Gregg 197; 
Pringle 2237): also specimens cultivated in Harvard Bot. Gard., 1882; 
and in Mo. Bot. Gard., 1882. 
21. Hchinocactus hamatocanthus brevispinus (Engelm.). 
Echinocactus longihamatus brevispinus Engelm. Syn. Cact, 274 (1856). 
Spines more slender than in longihamatus; radials 8 to 11, 1 to 5 em. 
long; centrals 4, terete, 3.5 to 5 em. long, the lowest hooked and searcely 
exceeding the radials. —Type unknown. 
In the “Great Bend” region of Texas and westward to New Mexico. 
Specimens examined: TEXAS (Wright of 1851): NEw MEXIco (Neal- 
ley of 1891). 
These three forms of hamatocanthus simply express extreme variations, as there is 
the greatest variation in spine characters. The type is a Mexican one, crossing the 
Rio Grande at the “Great Bend,” and reported as far west as E] Paso in but a single 
case, From its occurrence in Chihuahua, however, all the forms may be expected in 
the El Paso region. Doubtless all the forms occur in Mexico, but I have seen hama- 
tocanthus ané brevispinus only from the Texan side of the Rio Grande. 
++ + Central spines not annulate. 
= One central spine (generally the upper one) elongated and mostly white. 
22. Bchinocactus uncinatus Gal.; Pfeiff. Abbild. ii, t. 18 (1848-50). 
Glaucescent, globose to oblong: ribs 13, obtuse, tuberculate-inter- 
rupted: radial spines 7 or 8, 2.5 to5 em, long, the upper 4 or 5 straw-color, 
straight, flattened, the lower 5 purplish, terete, and hooked; centrals 4 
the upper 3 rather stout and straight, about 2.5 cm. long, the lowest 
one very long, flattened, hooked at apex: flowers brownish-purple: 
fruit ovate, 1.5 to 2.5em. long: seeds much compressed, curved, smooth . 
and shining, 1.2 to 1.4 mm. long. (Jl. 1. ¢.; Cact. Mex. Bound. t. 74, 
fig. 9, seed)—Type unknown. 
Chihuahua, Coahuila, and San Luis Potosi. 
Specimens examined: COAHUILA (Gregg 617; Poselger of 1850): SAN 
Luis Porost (Gregg 585): also specimens cultivated in Goebel’s Gard. 
(St. Louis), 1845; and in Hort. Pfersdorf in 1869. 
The usual reference of this name to Hopf. in Foerst. Handb, 321 (1846) is found to 
be a nomen nudum. 
23. Echinocactus uncinatus wrightii Engelm, Syn. Cact. 272 (1856). 
Oval, 7.5 to 15 em. high, 5 to 8.5 em. in diameter: radial spines 5, 
arranged as in the last; central spine solitary, angled, flexuous and 
hooked, elongated (5 to 15 em.), erect, straw-color with dark tip: 
flowers 2.5 to 3.5 em. long, dark-purple: fruit reddish: seeds curved, 
contracted at base, keeled on the back, tuberculate, 1.4 to 1.6 mm. long. 
(IU. Cact, Mex. Bound. t. 74. fig. 10, seed)—Type, Wright and Bigelow 
specimens in Herb. Mo. Bot. Gard. 
Abundant from El Paso, Texas, to the Pecos, but extending almost to 
the mouth of the Rio Grande, and southward into Chihuahua, 
