946 CONTRIBUTIONS FEOM THE NATIONAL HERBARIUM. 



coming indistinct in age, somewliat undulate ; areoles brown-felted when young ; 

 radial spines ascending, about 10, often tlireadlike; central spines subulate, 

 about 6, brown at first, somewhat flattened, annulate, often 6 cm. long; flowers 

 3.5 to 4 cm. long ; inner pertanth segments oblong, acute, yellowish ; scales on 

 ovary broad, rounded at tip ; fruit 2 to 2.5 cm. long ; seeds black, oblong, 1.5 mm. 

 long. 



17. Ferocactus echidne (DC.) Britt. & Rose, Cactaceae 3: 136. 1922. 

 Echinocactus echidne DC. Mgm. Cact. 19. 1834. 



Echinocactus vanderaeyi 'Leva. Cact. Aliq. Nov. 20. 1838. 



Echinocactus dolichanthus Lem. Cact. Aliq. Nov. 25. 1838. 



Echinocactus gilvus Dietr. Allg. Gartenz. 13: 170. 1845. 



Echinocactus victoricnsis Rose, Contr. U. S. Nat. Herb. 12: 291. 1909. 



Tamaulipas to Hidalgo ; type from Hidalgo. 



Depressed-globose, 12.5 cm. high, 18 cm. in diameter, green ; ribs 13, acate, 

 broad at base; areoles remote, velvety when young, oval; radial spines rigid, 

 about 7, about 2 cm. long, yellow ; central spine solitary, porrect, 3 cm. long 

 or more ; flowers lemon-yellow ; perianth segments linear-oblong, acute, some- 

 times toothed near apex; scales on the ovary ovate, acute. " Biznaga " (Ta- 

 maulipas). 



18. Ferocactus alamosanus Britt. & Rose, Cactaceae 3: 137. 1922. 

 Echinocactus alamosanus Britt. & Rose, Contr. U. S. Nat. Herb. 16: 239. 



1913. 



Sonora. the type from Alamos. 



Plants usually single, sometimes in clusters, somewhat flattened above, green, 

 30 cm. in diameter or more ; ribs about 20, narrow ; spines all yellow ; radials 

 usually 8, 3 to 4 cm. long, more or less spreading; central single, porrect or 

 erect, somewhat flattened laterally, 6 cm. long and a little longer than ilie 

 radials; flower buds covered with ovate ciliate scales, these brownish except 

 in the margin. 



19. Ferocactus g'laucescens (DC.) Britt. & Rose, Cactaceae 3: 137. 1922. 

 Echinocactus glaucescens DC. M6m. llus. Hist. Nat. 17: 115. 1828. 

 Echinocactus pfeifferi Zucc. ; Pfeiff. Enum. Cact. 58. 1837. 



Eastern central Mexico ; type from Tolimdn. 



Globular, 20 to 40 cm. in diameter, or a little higher thf\n broad, glaucous; 

 ribs 11 to 15, somewhat flattened, acute, 2 to 3 cm. high ; areoles 8 to 12 mm. 

 apart, oblong, 12 to 20 mm. long, yellowish, tomentose when young; radial 

 spines 6, nearly equal, rigid, only slightly spreading, straight, 2.5 to 3 cm. 

 long, pale yellow at first, when old blackish, more or less banded ; central 

 spine solitary, similar to the radials ; flowers yellow, 2 cm. long, perhaps 

 broader when fully expanded ; outer perianth segments ovate, acuminate, some- 

 times brownish on the back, ciliate ; inner perianth segments oblong, usually 

 only acute, somewhat toothed or lacerate ; scales on the ovary brownish, ovate, 

 acute, ciliate, imbricate. 



20. Ferocactus flavovirens (Scheidw.) Britt. & Rose, Cactaceae 3: 138. 1922. 

 Echinocactus flavovirens Scheidw. Allg. Gartenz. 9: 50. 1841. 



Vicinity of Tehuacrin, Puebla. 



Plant cespitose, forming great masses, pale green, 30 to 40 cm. high; stems 

 10 to 20 cm. in diameter; ribs 13, rarely 11 or 12, 1 to 2 cm. high, acute, 

 somewhat sinuate; areoles 2 cm. apart, large, grayish, woolly; spines pale 

 brown, becoming gray in age, long and stout; centrals 4, much longer than 

 the radials, somewhat unequal, the longer ones 5 to 8 cm. long; flower buds 

 globular, covered with long linear imbricate scales, their margins ciliate with 

 long hairs. 



