Mamillaria pusilla texana Engelm. Syn. Cact. 216 (1856).
Mamillaria texana Young, Fl. Texas, 279 (1873).
Ovate-globose, 2.5 to 3 cm. in diameter, 2.5 to 6 cm. high,
proliferous and at length cespitose: tubercles 7 to 9 mm. long,
the long axillary wool intermixed with several coarse twisted
bristles: radial spines very numerous, in many series, the outer
ones (30 to 50) capillary, white, elongated and flexuous or
crisped (12 to 16 mm, long when straightened), the inner ones (10
to 12) more rigid, shorter (6 to 8 mm.), puberulent, whitish or
yellowish, usually dark-tipped; central spines 5 to 8, rigid,
straight, pubescent, unequal, white below and reddish or dark
above: flowers 1.5 to 2 cm. long, the yellowish-white petals with
reddish median band: fruit 1.5 to 2 cm. long: seeds black and
shining, conspicuously pitted, 1.2 mm. long. (Ill. Cact. Mex.
Bound. t 5.) Type, Bigelow specimens in Herb. Mo. Bot. Gard.
From the mouth of the Rio Grande to El Paso, Tex., and southward
into Coahuila and Chihuahua. Fl. March-May.
Specimens examined: Texas (Bigelow of 1853; Nealley of 1892):
Coahuila (Bigelow of 1853): also growing in Mo. Bot. Gard. 1892
and 1893.
The exterior capillary spines cover the whole plant as with a
coarse wool.