STANDLEY TREES AND SHRUBS OF MEXICO. 969 



Simple, nearly globose, either obtuse or depressed at apex, 7.5 cm. in di- 

 ameter ; tubercles ovoid, large ; axils of tubercles naked ; areoles glabrate ; 

 spines all radial, 16 to 18, white or sometimes yellowish, 10 to 12 mm. long, 

 rigid, tomentose when young; flowers lemon-yellow, with outer segments tinged 

 with red, about 10 cm. broad, the segments narrowly oblong to spatulate, 

 acute, somewhat toothed toward the apex. " Huevos de coyote" (Patoni). 



21. Coryphantlia sulcolanata Lem. Cact. 35. 1868. 

 Mammillaria sulcolanata Lem. Cact. Aliq. Nov. 2. 1838. 

 Mammillaria convinanima Linke, Allg. Garteuz. 25: 239. 1857. 

 Mammillaria cornimximtna N. E. Brown, Gard. Chron. III. 2: 186. 1887. 

 Mexico, the range unknown; type said to have come from Mineral del 



Monte, Hidalgo. 



Subglobose, somewhat depressed, cespitose, 5 cm. high, 6 cm. thick or more; 

 tubercles somewhat 5-angled at base, subconic above, their axils very woolly 

 when young; spines 9 or 10, all radial, unequal, 12 to 16 mm. long, the 

 lower and upper weaker and shorter than the lateral ones, brownish with 

 black tips but when young whitish yellow with purple tips ; flowers 4 cm. 

 long or more, widely spreading, 6 cm. broad or more ; perianth segments 

 oblong, acute. 



22. Coryphantha retusa (Pfeiff.) Britt. & Rose, Cactaceae 4: 38. 1923. 

 Mammillaria retusa Pfeiff. Allg. Gartenz. 5: 369. 1837. 



Oaxaca. 



Plants depressed-globose, 5 to 10 cm. in diameter,^ the top very woolly ; 

 tubercles rather large; areoles elliptic; spines 6 to 12, all radial, ap- 

 pressed or even curved backward, yellowish to brownish, subulate except 

 2 or 3 aciculate ones at the upper part of areoles; flowers central, yellow, 

 about 3 cm. long; inner perianth segments oblong, acute. 



23. Coryphantha palmeri Britt. & Rose, Cactaceae 4: 39. 1923. 

 Durango, Coahuila, and Zacatecas ; type from Durango. 



Plant body globular; tubercles closely set in about 13 rows but not very 

 regularly arranged, pale green, not very flaccid; radial spines 11 to 14, 

 rather stout, spreading nearly at right angles to the central one, yellowish, 

 the tips often blackish ; central spine one, stout, terete, hooked at apex ; 

 young areoles very woolly ; flowers central, pale yellow to nearly white, 

 about 3 cm. long; outer perianth segments linear-oblong, acute, brownish on 

 the broad midrib, entire, the inner yellow throughout, acuminate. 



24. Coryphantha cornifera (DC.) Lem. Cact. 35. 1868. 

 Mammillaria cornifera DC. M§m. Mus. Hist. Nat. 17: 112. 1828. 

 Mammillaria pfeiff eriana De Vriese, Tijdschr. Nat. Gesch. 6: 51. 1839. 

 Mammillaria scolymoides Scheidw. Allg. Gartenz. 9: 44. 1841. 

 Coahuila and Querelaro, and elsewhere in central Mexico. 



Plant solitary, globose, pale green ; tubercles short, broad, somewhat im- 

 bricate, 12 cm. high ; radial spines 16 or 17, grayish, 10 to 12 mm. long ; central 

 spine 1, stout, erect or subincurved, generally dark-colored, 14 to 16 mm. long ; 

 flowers yellow, tinged with red, 7 cm. broad ; inner periantli segments ob- 

 lanceolate, acuminate. 



25. Coryphantlia salm-dyckiana (Scheer) Britt. & Rose, Cactaceae 4: 39. 

 1923. 



Mammillaria salm-dyckiana Scheer; Salm-Dyck, Cact. Hort. Dyck. 1849. 134. 



1850. 

 Mammillaria delaetiana Quehl, Monatsschr. Kakteenk. 18: 59. 1908. 

 Chihuahua. 



