Subglobose, 3.5 to 6.5 cm. high, simple: tubercles slender and terete, spreading, lightly grooved even to the base, 8 to 10 mm, long: radial spines 30 to 50, mostly in two series, straight and loosely spreading, the exterior ones (25 to 35) capillary and white, 6 to 18 mm. long, the interior ones (7 to 13) stiffer (setaceous), longer and darker and black-tipped; the central spine straight and porrect, 12 to 20 mm. long, often wanting: flowers small, red: fruit ovate, small (8 to 10 mm. long?): seeds globose-angled, almost black, pitted, 0.8 to 1.2 mm. long (Ill. Cact. Mex. Bound. t. 12. figs. 17-22) Type, Wright 110 in Herb. Mo. Bot Gard. From Eagle Pass, Texas, westward to El Paso and southern New Mexico, and southward into Chihuahua. Specimens examined: Texas (Wright 110 of 1852): New Mexico (Vasey of 1881; Mearns of 1892, in Big Hatchet Mountains) Chihuahua (Pringle 251 of 1885, in part). Pringle 251 as distributed to Nat. Herb. is C. tuberculosus. 52. Cactus maculatus, sp. nov. Obovate-cylindrical, 6 by 8 cm., somewhat cespitose: tubercles ovate, terete, 10 mm. long, grooved to the base, with naked axils: radial spines 10 or 11, straight and spreading, rigid, blackish (becoming ashy with age), black-tipped, 12 mm. long; central spine large, more or less spotted, erect, 25 to 35 mm. long: flower 13 mm. long, pinkish: fruit unknown. Type in Herb. Coulter. San Luis Potosi. Specimens examined: San Luis Potosi (Eschanzier of 1891). Somewhat resembles C. tuberculosus in general appearance, but very different in spine characters. 53. Cactus brunneus, sp. nov. Obovate-cylindrical, 3 by 6 cm., simple: tubercles ovate, grooved to the base, 5 to 6 mm. long, with woolly axils: radial spines 11 to 15, spreading, rather rigid and brownish (lighter with age), 8 to 10 mm. long; central spine much larger, 20 mm, long, hooked: flower and fruit unknown. Type in Herb. Coulter. San Luis Potosi. Specimens examined: San Luis Potosi (Eschanzier of 1891). ++ Central spines 3 to 12. 54. Cactus conoideus (DC.) Kuntze, Rev. Gen. Pl. 260 (1891). Mamillaria conoidea DC. Rev. Cact. 112 (1829). Mamillaria strobiliformis Engelm. Wisliz. Rep. 113 (1848), not Scheer (1850). Ovate-conical, 3.5 to 10 cm. high, 4 to 7 cm. in diameter below, with densely woolly vertex, simple: tubercles conical, about 12 mm, long, closely appressed-imbricate ("giving the plant the appearance of a pineapple or cone"): radial spines 10 to 16, ashy to white, straight and stout, 6 to 10 mm. long, the upper longer (10 to 15 mm.); central spines 3 to 5, stouter, brownish-black, 10 to 16 mm. long, the two or three smaller ones erect-spreading, the single lower one more rigid, porrect or deflexed, 15 to 20 mm. long: flowers 2 to 3 cm long and wide, deep purple: fruit unknown. (Ill. DC. Mem. Cact. t. 2) Type unknown. On rocks, Coahuila and Nuevo Leon to San Luis Potosi and southern Mexico.