Mamillaria similisEngelm. Pl. Lindh. 246 (1845).Mamillaria nuttallii caespitosaEngelm. Syn. Cact. 265 (1856).
Mamillaria missouriensis caespitosaWatson, Bibl. Index,403 (1878).
Cespitose, with 12 to 15 puberulent radial spines, the central very often wanting, larger flowers (2.5 to 5 cm. long), fruit and seeds (1.6 to 2.2 mm. in diameter), and 5 stigmas. (Ill. Cact. Mex. Bound. t. 74. f 7, seeds)Type, Lindheimer, of 1845 (?) in Herb. Mo. Bot. Gard.
From the Kansas River, Kansas, and eastern Colorado, southward through Oklahoma to the San Antonio River, Texas.
Specimens examined: Colorado (Greene of 1870): Kansas (Carleton551of1891,fromKingmanCounty,distributedasMamillariadasyacantha): Oklahoma (Carleton 120 of 1891): Texas (Lindheimer of 1845, 1850; Wright of 1850; Reverchon 725): also specimens cultivated in Goebel's Garden in 1846; and in St. Louis in 1846, 1847, 1851.The cespitose masses are often a foot broad.
39.Cactus missouriensis robustior (Engelm.).
Mamillaria similis robustior Engelm. Pl. Lindh. 200 (1850). Mamillaria nuttallii robustiorEngelm. and Bigel. Pacif. R.Rep. iv. 28 (1856).Mamillaria missouriensis robustiorWatson, Bibl. Index,440 (1878).
Almost simple, with longer aid looser tubercles, 10 to 12 stouter radial spines (6 to 16 mm. long), a single stout central, larger flowers, and 7 or 8 stigmas.Type, Lindheimer of 1845 in Herb. Mo. Bot. Gard.
From southeastern Colorado and the Canadian River (Oklahoma and Indian Territory), to the Colorado River of Texas.
Specimens examined: Texas (Lindheimer of 1845, 1846; Bigelow of 1853): also specimens cultivated in St. Louis in 1847.
In Bigelow's specimens the central spine is mostly lacking.
40.Cactus scheerii(Muhlenpf.) Kuntze, Rev. Gen. Pl. 261 (1891).
Mamillaria scheeriiMuhlenpf. Allg. Gart. Zeit. xv. 97 (1847). Mamillaria scheerii validaEngelm. Syn. Cact. 265 (1856).
Ovate-globose, 7.5 to 17.5 cm. high, 7.5 to 12.5 cm. in diameter, simple or sparingly proliferous at base: tubercles large (2.5 to 3.5 cm. long), from a broad base and suddenly contracted and almost cylindric (10 to 14 mm. in diameter), deeply grooved (1 to 5 orbicular glands in the groove), distant, spreading and ascending, the lower ones shorter, more conical and somewhat imbricated, with broad axils and the younger densely woolly: radial spines 6 to 16, straight or slightly curved, stout, rigid, bulbous at base, whitish or yellowish (sometimes reddish) with dark tip, the 2 to 5 lower and lateral ones stouter and compressed (18 to 30 mm. long), the 4 to 11 upper ones weaker and terete (10 to 20 mm. long); central spines 1 to 5, stout and angled, 20 to 36 mm. long,,mostly yellow (sometimes reddish), a single one very stout and porrect: flowers 5 cm. long, yellow (sometimes reddish tinged): fruit ovate or subglobose, green: seeds large (3 mm. long), flat and obovate, red.Type unknown; that of the old var. valida is the Wright material in Herb. Mo. Bot. Gard.
Sandy ridges, southwestern Texas, from Eagle Pass and head of the Limpia to El Paso, and southward into Chihuahua, Coahuila, and San Luis Potosi; also southern Mexico (fide Hemsley).Fl. July.
Specimens examined: Texas (Wright 416, 478, of 1851, 1852; Evans of 1891): San Luis Potosi (Eschanzier of 1891).
The var. valida was described by Dr. Engelmann without having seenC. scheerii, the only knowledge of that species being obtained from the description of Prince Salm-Dyck in Cact. Hort. Dyck., which seemed to indicate a smaller form, with fewer spines than the Texan form.However, when visiting the collections of Prince Salm-Dyck, Dr. Engelmann found original specimens of C. scheerii which were exactly his var. valida.So far as collections show the Texan form seems to be more robust than the Mexican, but the material is too scanty to justify such a generalization.Dr. Engelmann speaks of this species as "a stately plant, by far the largest, of the northern Mamillariae"Its tubercles are bright green and in beautiful contrast with the showy yellow spines.
41.Cactus robustispinus (Schott) Kuntze, Rev. Gen. Pl. 261 (1891).
Mamillaria robustispinaSchott in Engelm. Syn. Cact. 265 (1856).
A large stout plant, simple or cespitose: tubercles large, subterete, nearly 2.5 cm. long (and about the same distance from each other): radial spines 12 to 15, stout and rigid, 18 to 30 mm. long, the lower ones the stouter, more dusky, straight or often curved downwards, the upper straight and fascicled; the solitary central spine stout, compressed, curved downwards (occasionally an additional straighter upper one), not much longer than the radials, the base nearly 2 mm. wide; all the spines horny and black-tipped; flowers 3.5 to 5 cm. long with very slender and constricted tube, saffron-yellow: fruit green seeds large (3 to 3.2 mm, long and 2 mm. in diameter), obliquely obovate and curved, smooth and brownish. (Ill. Cact. Mex. Bound. t. 74. fig. 8, seeds)Type, Schott specimens in Herb. Mo. Bot. Gard.
"On grassy prairies on the south side of the Babuquibari Mountains," Sonora.Fl. July.
Specimens examined: Sonora (Schott of 1853-4).
Dr. Engelmann remarks that the seeds of this species are larger thanthose of any other Mamillaria known to him.
42.Cactus recurvatus (Engelm.) Kuntze Rev. Gen. Pl. 259 (1891).
Mamillaria recurvispinaEngelm. Syn. Cact. 265 (1856), not Vries.Mamillaria recurvataEngelm. Trans. St. Louis Acad. ii. 202 (1863).
