99 
and made to bloom, showing the flowers to be larger and darker colo#ed than in the 
rest of the group, from which the species also differs in its more robust habit, its 
very unequal radial spines, and the occasional occurrence of two centrals, 
** Central spine hooked. 
9. Cactus uncinatus (Zucc) Kuntze, Rev. Gen, PI. 261 (1891). 
Mamillaria uncinata Zuce. in Pfeiff. Enum, 34 (1837). 
Mamillaria bihamata Pfeiff. in Otto and Deitr. Gart. vi. 274 (1840). 
Mamillaria adunca Scheidw. (1845-1819?). 
Mamillaria depressa Scheidw. (1845-1849?). 
Usually globose (occasionally depressed or even subcolumnar), 5 to 
6 em. in diameter (doubtless becoming larger): tubercles 8 to 10 min, 
long, woolly in the upper axils: radial spines 4 to 6, rigid, 4 to 6 mm, 
long, the upper one stouter than the rest and sometimes shorter, red- 
dish-brown and horny, straight or slightly curved, the remainder 
straight and white with dusky tips; central spine stout and horny, 
reddish-brown, 7 to 10 mm. long: flowers greenish-white or tinged with 
red: fruit unknown—Type unknown. 
Entirely Mexican, reported from Chihuahua to San Luis Potosi. 
Specimens examined: San Luis Porost (Gregg of 1548; Parry 268, 
Eschanzier of 1891): CHIHUAHUA ( Wislizenus of 184647; also Chihua- 
hua specimens cultivated in the Jacoby Garden in 1856 and 1857). 
The variations observed in this species do not seem sufficient for the establishment 
of varieties. The type form seems to have been globose, with 4 radial spines and a 
stout central one. The depressed forms with 6 radials and a more slender central 
represent var. spinosior Lem. (M. depressa Scheidw.); and the subcolumnar forms 
with 6 radials (the upper one of which is somewhat curved) and a stout strongly 
hooked central represent var biuncinata Lem. (M. bihamata Pfeiff.). Such combina- 
tions of characters, however, do not hold, as any one of the plant body forms may dis- 
play any one of the spine characters referred to. 
B. Tubercles terete. 
* Central spines none: moatly simple globose plants, with veru numerous straight whitish 
setaceous radials. 
10. Cactus lasiacanthus (Engelm.) Kuntze, Rev. Gen. PJ. 259 (1891). 
Mamillaria lasiacantha Kngelm. Syn. Cact. 261 (1856). 
Globose or ovate globose, 2 to 2.5 em, high and 1 to 2 em. broad: 
tubercles 4 mm. long, about 2 mm. in diameter, with naked axils: spines 
40 to 60, in many series, very unequal, 2 to 4 mm. long, white and 
pilose, the upper exterior usually longer than the rest, the innermost 
usually much shorter: flowers 12 mm. long, whitish or pinkish (petals 
with red median band): fruit 1 to 2 cm. long: seeds about 1 im. long, 
blackish and conspicuously pitted. (JU. Cact. Mex, Bound. t. 5)—'Type, 
the specimens of Wright in Herb. Mo. Bot. Gard. 
From western Texas (‘west of the Pecos, on low limestone hills, 
among herbage”) to Arizona and Chihuahua, I'l. April, May. 
