STANDLEY TEEES AND SHRUBS OF MEXICO. 931 



26. ARIOCARPUS Scheidw. Bull. Acad. Brux. 5: 491. 1838. 



Plants spineless, usually simple, low, with flat or round top ; tubercles tough, 

 horny, or cartilaginous, triangular, imbricate, spirally arranged, the lower part 

 tapering into a claw, the upper or bladelike part expanded; areoles terminal 

 or at the bottom of a triangular groove near the middle of tubercle, filled with 

 hair when young; flowers appearing from near the center on young tubercles, 

 diurnal, rotate-campanulate, white to purple ; fruit oblong, smooth ; seeds 

 black, tuberculately roughened, with a large basal hilum ; embryo described as 

 obovate, straight. 



The following are the only species known : 



Tubercles not grooved on upper side 1. A. retusus. 



Tubercules grooved on the upper side. 



Plants small, 3 to 5 cm. bi'oad 2. A. kotschoubeyanus. 



Plants large, 10 to 15 cm. broad 3. A, fissuratus, 



1. Ariocarpus retusus Scheidw. Bull. Acad. Brux. 5: 492. 1838. 

 Anhalonium prism at icum Lem. Cact. Hort. Monv. 1. 1839. 

 Anhalonium retusum Salm-Dyck. Cact. Hort. Dyck. 1844. 15. 1845. 

 Anhalonium elongatum Salm-Dyck, Cact. Hort. Dyck. 1849. 77. 1850. 

 Anhalonium areolosum Lem. Illustr. Hort. Lem. 6: Misc. 35. 1859. 

 Anhalonium, pulvilligerum, Lem. Illustr. Hort. Lem. 16: Misc. 72. 1869. 

 Mamillaria areolosa Hemsl. Biol. Centr. Amer. Bot. 1: 503. 1880. 

 Mam,illaria elongata Hemsl. Biol. Centr. Amer. Bot. 1: 509. 1880. 

 Mamillaria prism-atica Hemsl. Biol. Centr. Amer. Bot. 1: 519. 1880. 

 Mamillaria furfuracea S. Wats. Proc. Amer. Acad. 25: 150. 1890. 

 Anhalonium trigonum Weber, Diet. Hort. Bois 90. 1893. 



Coahuila, Zacatecas, and San Luis Potosl 



Plants globular or more or less depressed, usually 10 to 12 cm. broad, grayish 

 green to purplish, very woolly at the center ; tubercles horny, imbricate, 5 cm, 

 long or less, ovate, more or less 3-angled, acute to acuminate, often with a 

 woolly areole on the upper skle near the tip and this sometimes spinescent; 

 flowers borne at the axils of young tubercles near the center, white or nearly 

 so, up to 6 cm. long; outer perianth segments pinkish, narrow, acute to 

 acuminate; inner perianth segments at first white, afterwards pinkish, 

 narrowly oblanceolate, with mucronate tip ; fruit oblong, white, naked ; seeds 

 globular, 1.5 mm. in diameter, black, tuberculate-roughened. " Chaute,"^ 

 " chautle." 



According to Ochoterena, the name " peyote " is sometimes erroneously ap- 

 plied to this species. 



2. Ariocarpus kotschoubeyanus (Lem.) Schum. in Engl. & Prantl, Pflanzen- 



fam. Nachtr. 259. 1897. 



Anhalonium kotschoubeyanum Lem. Bull. Cercl. Confgr. Hort. Seine. 1842. 



Anhalonium, sulcatum Salm-Dyck, Cact. Hort. Dyck. 1849. 5. 1850. 



Central Mexico. 



Plants grayish green, 3 to 5 cm. broad, only the flat crown appearing above 

 the surface of the ground, with a thickened fleshy rootstock, and with several 

 spindle-shaped roots from the base; upper part of tubercle flattened, triangu- 

 lar, 6 to 8 mm. long, grooved along its middle almost to the tip, the groove 

 very woolly ; flowers 2.5 to 3 cm. long, originating in the center of the plant 

 from the axils of the young tubercles, surrounded by a cluster of hairs ; outer 

 perianth segments few, brownish, obtuse; inner perianth segments up to 2 

 cm. long, oblanceolate, obtuse or apiculate, sometimes retuse, rose-colored to 

 light purple, widely spreading ; ovary naked ; seeds oblong, 1 mm. long. " Pe- 

 zufia de venado " (Nuevo Le6n). 



