124 



THE CACTACEAE. 



Key to Species continued. 



Central spine straight or more or less curved, but not hooked. 

 Central spines flexible, thin. 



Central spines more or less appressed; seeds very small, not angled, less 



than 2 mm. long 



Central spines more or less tortuous and spreading ; seeds larger than those 



of F. lecontei, more than 3 mm. long 



Central spine dagger-like, straight, erect 



BB. Areoles without marginal hairs or bristles. 



Spines all alike 



Radial spines different from the central. 

 Central spines more or less hooked. 



Central spine 1 



Central spines 4 



Central spines not hooked. 



Flowers lemon- yellow; inner perianth-segments elongated 



Flowers crimson; perianth-segments all short 



AA. Plants much smaller than the last, 6 dm. in diameter or less, sometimes, how- 

 ever, forming large clumps. 



Areoles with stout spines and weak bristles 



Areoles with stout spines only. 

 Spines never hooked. 

 Spines all straight. 



Scales on ovary broader than linear and not with long ciliate margins. 

 Flowers 4 to 5 cm. long, large; plant green. 



Plant flattened; ribs acute; margin of scales of ovary not ciliate .... 



Plant rounded; ribs obtuse; margin of scales of ovary ciliate 



Flowers 2 cm. long, small; plant glaucous 



Scales on ovary linear, with long ciliate margins 



Spines more or less curved. 



Flowers small, 3.5 cm. long or less; ribs up to 24 



Flowers larger; ribs fewer than in the last. 



Scales on ovary acute 



Scales on ovary obtuse. 



Central spines strongly flattened 



Central spines nearly terete 



Some of the spines hooked or recurved at the top. 

 Central spines or one of them broad and short. 



Central spine solitary 



Central spines several. 



Radial spines all straight 



Radial spines on lower side of areoles hooked 



Central spines slender and elongated. 



Flowers large, yellow 



Flowers small, pinkish to brownish 



AAA. Species not grouped 



8. F. lecontei 



9. F. acanthodes 



10. F. santa-maria 



11. F. diguelii 



12. F. covillei 



13. F. peninsulat 



14. F. rectispinus 



15. F. orcuttii 



16. F. robustus. 



17. F. echidne 



1 8. F. alamosanus 



19. F. glaucescens 



20. F. flavovirens 



21. F. melocactiformis 

 12. F. macrodiscus 



23. F. viridescens 



24. F. johnsonii 



25. F. nobilis 



26. F. latispinus 



27. F. crassihamatus 



28. F. hamatacanthus 



29. F. uncinatus 



30. F. roslii 



1. Ferocactus stainesii (Hooker). 



Echinocactus stainesii Hooker in Audot, Rev. Hort. 6: 248. 1845. 

 Echinocaclus pilosus Galeotti in Salm-Dyck, Cact. Hort. Dyck. 1849. 148. 



1850. 

 Echinocactus pilosus steinesii* Salm-Dyck, Cact. Hort. Dyck. 1849. 149. 



1850. 



Simple or proliferous, globular to columnar, up to 1.5 meters high; 

 ribs 13 to 20, compressed, more or less undulate; areoles distant, circular; 

 radial spines reduced to long white hairs; central spines several, subulate, 

 at first purplish, becoming pale yellow in age; flowers yellow; fruit 

 unknown. 



Type locality: Not cited. 



Distribution: San Luis Potosi, Mexico. 



This species differs from the following one in having more 

 distant ribs, the areoles more widely separated, the spines duller 

 colored, more numerous, somewhat curved, two of them decidedly 

 flattened and the hairs white. We know the plant only from 

 description and illustrations. 



"This plant was named for Fred. Staines whose name is sometimes wrongly spelled Staine and Steins and hence the 

 specific name steinsii used by Salm-Dyck is incorrect. 



Fig. 128. Section of rib of 

 Ferocactus stainesii. 



