The North American Species of Cactus, Anhalonium, and Lophophora | Page 8

mm.
long; in young plants and on lower tubercles of adult plants about 20,
equal and radiant; on flower-bearing tubercles 30 to 40, stellate-porrect
in every direction, the 6 to 8 upper ones two to four times longer than
the rest (4 to 8 mm.), clavate toward the apex and acute (the clavate top
at length deciduous), intermixed with loose wool of about the same
length and forming a small tuft on the top of the plant which includes
and partly hides flowers and fruit: flowers whitish to light pink, almost
central, very small (6 mm. in diameter), much reduced (3 to 5 sepals, 5
petals, 10 to 15 stamens, 3 stigmas): fruit 8 to 12 mm. long: seeds 1.5
mm. long, black and shining. (Ill. Cact. Mex. Bound. t. 1 and 2. figs.
1-4) Type, the specimens of Wright in Herb. Mo. Bot. Gard.
On naked mountain tops and sides, extreme southwestern Texas (Val
Verde County to El Paso) and southward into Coahuila and Chihuahua.
Specimens examined: Texas (Wright 227 of 1849, also of 1852;
Nealley of 1892): Coahuila (Bigelow of 1853): Chihuahua (Pringle
212): also growing in Mo. Bot. Gard. 1893.
The plants densely covered above with delicate ashy-gray spines and
with naked tuberculate base are readily recognized. It still remains an
open question whether the flowers are developed from the axils of
tubercles of the same season or the last ones of the preceding season.
Dr. Engelmann inclined to the latter view, as all the other characters of
the plant associate it with the "lateral-flowered" species; and in the
absence of definite observation we have retained it there. If the nearly
central flowers indicate that they are produced from growth of the same
season the species would seem to be allied to Coryphantha, in which
group its small flowers and small tubercles would be anomalous.
13. Cactus micromeris greggii (Engelm.).
Mamillaria micromeris greggii Engelm. Syn. Cact. 261 (1856).
Larger (2.5 to 5 cm. in diameter) and becoming oblong, with larger
globose-ovate tubercles (2 to 2.5 mm. long), fewer rigid spines all
radiant (interior 5 to 7 shorter and stouter, 1 to 2 mm. long; the outer 15
to 18, 3 to 4 mm. long), and fruit 1.5 to 2 mm. long. (Ill. Cact. Mex.
Bound. t. 2. figs. 5-8) Type, Gregg 508 in Herb. Mo. Bot. Gard.
Mountain ridges near Saltillo, Coahuila. Said by Budd to occur within

the southern borders of Pecos County, Tex.
Specimens examined: Coahuila (Gregg 508; Palmer of 1880).
It is a question whether this variety does not merely represent an older
and better developed plant than those upon which the species is based.
Mr. Harry I. Budd, who has made extensive collections of Texan and
Mexican Cacti for the market, reports that it is impossible to separate
sharply the variety from the species in the field, and regards the
difference merely as one of age. Unfortunately, only living material of
the species could be examined, but its characters seem well sustained
even in the most vigorous plants, some of which reach the size of the
variety. Through this variety the species is brought very near the
following:
14. Cactus bispinus.
Mamillaria microthele Muhlenpf. Allg. Gart. Zeit. p. 11 (1848), not
Lem. (1838).
Differs from the last form (var. greggii) chiefly in its cespitose habit,
much larger tubercles, and two unusually stout and short central spines
(fide Engelmann, who examined specimens in Coll. Salm-Dyck).
Credited to Mexico in general, but said by Budd to occur within the
southern border of Pecos County, Tex.
** Central spines present and one or more hooked. + Mostly globose
and simple plants (occasionally somewhat cylindrical).
15. Cactus wrightii (Engelm.) Kuntze. Rev. Gen. Pl. 261 (1891).
Mamillaria wrightii Engelm. Syn. Cact. 262 (1856).
Globose or depressed globose (top-shaped below), 3 to 7.5 cm. in
diameter, simple: tubercles 10 to 12 mm. long, with naked axils: radial
spines 8 to 12, white (the upper dusky-tipped), pubescent, 8 to 12 mm.
long central spines mostly 2 (usually side by side and divergent), rarely
1 or 3, scarcely longer, hooked and reddish-black: flowers 2.5 cm. long,
bright purple: fruit about 2.5 cm. long, somewhat subglobose, purple:
seeds 1.4 mm long, black and pitted. (Ill. Cact. Mex. Bound. t.8. figs.
1-8) Type, Wright of 1851 in Herb. Mo. Bot. Gard.
High plains and rocky places, from the Upper Pecos, east of Santa Fe,
N. Mex., southward through extreme southwestern Texas (between the
Pecos and El Paso), and into Chihuahua (near Lake Santa Maria).
Specimens examined: New Mexico (Wright of 1851; Rusby of 1880):
also growing in Mo. Bot. Gard. 1893.

Dr. Engelmann calls attention to the fact that this species is closely
allied to the Mexican C. zephranthoides (Scheidw.), but in the absence
of material representing the latter species no comparison can be made.