Ovate or ovate-cylindrical, 5 to 25 cm. high, 3.5 to 7.5 cm. in diameter, simple or rarely branching at base: tubercles ovate-cylindrical, 8 to 14 mm. long, with axillary bristle-bearing wool, at length naked: radial spines 30 to 60, in two series, the exterior bristle-like, shorter and white, the interior stouter, longer and dusky-tipped or purplish; central spines 3 or 4, stouter, longer, brown or blackish from a paler base, the upper 2 or 3 (10 to 14 mm. long) straight, or one or two or even all hooked, the lower stouter and longer (12 to 18 mm.), hooked upwards: flowers about 2.5 cm. long: fruit 1 to 2.5 cm. long: seeds large (1.2 to 1.5 mm. in diameter), globose and wrinkled, partly immersed in a brown spongy or corky cup-shaped 3-lobed appendage. (Ill. Cact. Mex. Bound. t. 7) Type, Parry of 1850, but modified by Le Conte 14 and Bigelow of 1854, all in Herb. Mo. Bot. Gard. Gravelly soil and sandy stream-banks, from the eastern slopes of the mountains of southern California, throughout western Arizona and southern Nevada to southern Utah; referred also to "N. W. Mexico" by Hemsley (Biol. Centr.-Amer.). Specimens examined: California (Parry of 1850; Newberry of 1858; Parish of 1882): Arizona (Le Conte 14; Bigelow of 1854; Dr. Loew of 1875: also Palmer of 1870, but with no locality. In the original description this species was confounded with C. grahami, with which it grows and which it much resembles; and this, together with the fact that 4 central hooked spines are seldom found, induced Dr. Engelmann (Syn. Cact. 262) to propose the more appropriate but untenable name M. phellosperma. The resemblance to C. grahami is not so close as general appearance would indicate, as the more oblong or cylindrical form, longer and less crowded tubercles, more numerous spines, often more than one hooked central, large seeds, and remarkable seed appendages serve well to distinguish it. ++ Plants with fasciculate slender cylindrical stems (30 to 45 cm. high, and 2.5 to 6 cm. in diameter): Lower Californian. 23. Cactus roseanus (Brandegee). Mamillaria longihamata Engelm. Mss. Mamillaria roseana Brandegee, Zoe, ii. 19 (1891). Fasciculately branched at base, the stems 30 to 45 cm. long (sometimes pendent from rocks and as much as 200 cm. long) and 2.5 to 5 cm. in diameter, the whole plant glaucous: tubercles elongated-conical, ascending, 10 to 12 mm. long, with woolly axils: radial spines 7 to 10, straight, rigid and sharp, 9 to 15 mm. long, dark reddish when young, becoming ashy, the upper ones the longer; the solitary central much longer (20 to 30 mm.), almost black below and with reddish tip, becoming ashy with age, usually hooked downwards: flowers numerous, 2.5 to 3.5 cm. long, bright scarlet: fruit obovate to globose, scarlet, 6 to 9 mm. in diameter, fleshy: seeds black and pitted. Type in Herb. Calif. Acad. Apparently common at low elevations throughout southern Lower California, especially the eastern side.