Dr. Engelmann observed a curious intermediate character in the origin of the flowers of this species, the first ones of the season appearing in the axils of the last tubercles of the preceding year, while the later ones develop from the axils of the first tubercles of the same season.The specimen growing in Mo. Bot. Gard, in 1893 had 3 central spines, one or two being hooked.
19.Cactus grahami (Engelm.) Kuntze, Rev. Gen. Pl. 260 (1891).
Mamillaria grahamiEngelm. Syn. Cact. 262 (1856).
Globose or at length ovate, 2.5 to 7.5 cm. high, simple or branched from the base and even cespitose: tubercles ovate, 6 mm. long, dilated at base (corky and persistent when old), with naked axils: radial spines 15 to 30 in a single series, white, often dusky-tipped, slender but rigid, naked or puberulent, 6 to 12 mm. long, the shorter ones uppermost, the longer ones lateral; central spines 1 to 3, blackish from a paler base, the lower (often the only) one stouter and longer (6 to 18 mm.), hooked upward, the one or two upper ones (when present) shorter and slenderer, divergent: flowers 2 to 2.5 cm. long, rose-colored: fruit 2 to 2.5 cm. long: seeds 0.8 to 1 mm. long, black and pitted.(Ill. Cact. Mex. Bound. t. 6. figs. 1-8)Type, Wright of 1852 and Bigelow of 1852 in Herb. Mo. Bot. Gard.
In rocky places, from the mountains of extreme southwestern Texas (west of the Pecos) to southern Utah, southern California (common along the Colorado), and Sonora.Fl. June-August.
Specimens examined: Texas (Wright of 1852; Newberry of 1858; G. R. Vasey of 1881; Miller of 1881; Briggs of 1892): New Mexico (Evans of 1891): Arizona (Bigelow of 1852; Schott of 1858; Cous of 1865; Palmerof 1869, 1870; Engelmann of 1880; Pringle of 1884): Utah (Parry of 1874): Sonora (Schott of 1853): also specimens cultivated in the Mo. Bot. Gard. in 1881.
In all references to the fruit of this species it is described as "oval and green," except in Ives Report, where Dr. Engelmann describes its real character as the ordinary fruit of Eumamillaria.The immature fruit is "oval and green," but with maturity it becomes clavate and scarlet.The Utah specimens of Parry show an exceptional character in their 30 to 33 scabrous radial spines, but otherwise they are quite normal.M. microcarpa Engelm., Emory's Rep. 156. f. 3, should be dropped as a synonym of this species, at least as to figure and description. In all probability C.grahami is one of the forms of the Mexican C. schelhasii (Pfeiff.).Except that in C. grahami the radial spines are apt to be more numerous and longer, and the centrals much darker; and in C. schelhasii the 3 centrals seem to be always present and sometimes all hooked, the descriptions suggest no difference.In the absence of authentic specimens of the latter species,however, and with its fruit and seed entirely unknown, such a reference ofC. grahami must be deferred.
20.Cactus bocasanus (Poselger).
Mamillaria bocasanaPoselger, Gart. Zeit. 94 (1853).
Depressed-globose, 2 to 3 cm. high: tubercles 8 mm. long, with long axillary wool: radial spines 25 to 30, white and capillary, 10 to 25 mm. long; central spines 2 to 4, slender and naked (or slightly puberulent), the most central one hooked (usually upwards), 15 to 25 mm. long, the upper 1 to 3 shorter and straight, all yellow with red tips, the hooked one often brownish-red nearly to the base: flowers unknown: fruit green, about 4 mm. long: seeds cinnamon-brown, oblique, broadly obovate, with narrowly ovate basal hilum.Type unknown.
San Luis Potosi, so far as known.Poselger says, "Texas, auf der Seira de Bocas, among rocks," which station we have been unable to locate.
Specimens examined: San Luis Potosi (Eschanzier of 1891): also specimens cultivated in Hort. Pfersdorff in 1869; in Mo. Bot. Gard. in 1891; also growing in Mo. Bot. Gard. 1893.
The capillary radials give the plant a white-woolly appearance.The younger spines at the vertex are erect and tufted.It resembles C. grahami, but the tubercles are much more slender and not thickened at base, all the spines are more slender, the central hooked one is more reddish, and the fruit is much shorter.
21.Cactus eschanzieri, sp. nov.
Depressed-globose, 3 cm. in diameter, simple: tubercles broader at base, 6 to 8 mm. long, with naked axils: spines all pubescent; radials 15 to 20, with dusky tips, the lateral 10 to 12 mm. long, the lower weaker, shorter and curved, the upper shorter; solitary central spine reddish, slender, somewhat twisted, usually hooked upwards, 15 to 25 mm. long: flowers red (?): fruit reddish (?), ovate, about 10 mm, long: seeds reddish, oblique-obovate, 1.2 mm. long, pitted, with subventral hilum.Type in Herb. Coulter.
San Luis Potosi.
Specimens examined: San Luis Potosi (Eschanzier of 1891). Resembles C. grahami, but with fewer and more slender pubescentspines, longer and less rigid central, more exserted fruit, and much larger reddish and strongly pitted seeds with subventral hilum.
22.Cactus tetrancistrus (Engelm.).
Mamillaria tetrancistraEngelm. Am. Jour. Sci. II. xiv. 337 (1852), in part.Mamillaria phellospermaEngelm. Syn. Cact. 262 (1856).Cactus pellospermusKuntze, Rev. Gen. Pl. 261 (1891).
