STANDLEY TEEES AND SHRUBS OF MEXICO. 1001 



a few bristles ; flowers about 15 mm. long, purplish ; fruit red, clavate ; seeds 

 black, the surface deeply pitted. 



92. Neomammillaria albicans Britt. & Rose, Cactaceae 4: 138. 1923. 

 Islands of the Gulf of California ; type from Santa Cruz Island. 



Plants at first globose but becoming cylindric and then 10 to 20 cm. long, 

 up to 6 cm. in diameter, often in clumps of 5 to 15 plants ; spines almost hid- 

 ing the plant body and often pure white ; radial spines numerous, short, stiff, 

 widely spreading; central spines several, straight, stiff, often brownish or 

 blackish at tip ; spine areoles when young densely white-woolly ; fruit clavate, 

 red, 10 to 18 mm. long ; seeds black. 



93. Neomammillaria slevinii Britt. & Rose, Cactaceae 4: 139. 1923. 

 Islands of Baja California, the type from San Josef Island. 



Plants simple, cylindric, 10 cm. high or more, 5 to 6 cm. in diameter, en- 

 tirely hidden under the mass of closely set spines ; spines at the top of plant 

 pinkish below, with brown to blackish tips, those on the lower part of plant 

 bleaching white ; radial spines numerous, acicular, widely spreading ; central 

 spines about 6, a little longer and stouter than the radials, slightly spreading ; 

 flowers about 2 cm. broad ; outer perianth segments with a pinkish midrib, 

 the inner white ; fruit red, about 1 cm. long ; seeds black. 



94. Neomammillaria palmeri (Coulter) Britt. & Rose, Cactaceae 4: 140. 1923. 

 Mammillaria palmeri Coulter, Contr. U. S. Nat. Herb. 3: 108. 1894. 



San Benito Island and possibly Guadalupe Island, Baja California. 



Densely cespitose ; individuals small ; axils densely woolly and bristly ; 

 radial spines 25 to 30, slender, white, 5 mm. long, radiating; central spines 

 3 to 5, stouter and longer than the radials, brownish with black tips, 

 straight, 7 to 8 mm. long ; flowers cream-colored, sometimes tinged with pink ; 

 fruit clavate, scarlet ; seeds black. 



95. Neomammillaria uncinata (Zucc.) Britt. & Rose, Cactaceae 4: 140. 1923. 

 Mammillaria imcinata Zucc. ; Pfeiff. Enum. Cact. 34. 1837. 

 Mammillaria bihamata Pfeiff. Allg. Gartenz. 6: 274. 1838. 

 MammUlaria dcpressa Scheidw. Bull. Acad. Brux. 5: 494. 1838. 



Hidalgo and San Luis Potosi, and elsewhere in central Mexico. 



Globose or somewhat depressed, usually half-buried in the soil, 8 to 10 

 cm. in diameter ; tubercles lactiferous, short, obtuse ; axils of old tubercles 

 naked, of young ones lanate, forming a mass of wool at the top ; young 

 spine areoles also lanate ; radial spines 4 to 6, usually white, subulate, 4 to 

 5 mm. long; central spines usually solitary, sometimes 2 or 3, much stouter 

 than the radials, 8 to 12 mm. long, brown, hooked at apex ; flowers reddish 

 white, about 2 cm. long; inner perianth segments linear-oblong; fruit clavate, 

 10 to 18 mm. long, red ; seeds small, brown. 



96. Neomammillaria hamata (Lehm.) Britt. & Rose, Cactaceae 4: 140. 1923. 

 Cactus cylindricus Orteg. Hort. l\Iatr. Dec. 128. 1800. Not C. cylindricus 



Lam. 1783. 



Mammillaria hamata Lehm. ; Pfeiff. Enum. Cact. 34. 1837. 



Mexico, the range not known. 



Stem CO cm. long, cylindric, .somewliat branched at base, said to be milky; 

 tubercles conic or a little compressed; radial spines 15 to 20, white, spread- 

 ing; central spines several, brownish, stouter than the radials, one of them 

 hooked ; flowers small, probably scarlet, from near the top of the plant but 

 from the axils of old tubercles ; inner perianth segments lanceolate, acute ; 

 fruit slender, clavate, probably red ; seeds minute, brown. 



