8 THE cactaceae;. 



grayish lanate when young; radial spines 3 to 5, stout, purplish brown, i to 3 cm. long; central spines 

 wanting or solitary; flowers salmon to yellow, about 5 cm. broad; perianth-segments nearly linear, 

 acute; scales of ovary glabrous, 6 mm. long. 



Type locality: Near Chihuahua. 



Distribution: Chihuahua, Mexico. 



Our description is drawn mostly from the figure in Bliihende Kakteen, plate 126. 



We have seen flowering specimens of what is called this species at La Mortola, Italy. 

 Although the type came from Chihuahua, we have seen no plant from that region which 

 answers it. 



There is a plant in collections, passing as Echinocactus lophothele longispinus (Monats- 

 schr. Kakteenk. 15: 138. 1905), which we do not know. 



Illustrations: Schelle, Handb. Kakteenk. 196. f. 129; Bliihende Kakteen 3: pi. 126; 

 Weinberg, Cacti 12; Blanc, Cacti 48. No. 560, as Echinocactus lophothele. 



4. Thelocactus ph5niiatothele (Poselger). 



Echinocactus phymatothelos * Poselger in Forster, Handb. Cact. ed. 2. 602. 1885. 



Simple, depressed-globose, 5 cm. high, 9 to 10 cm. in diameter; ribs 13, glaucous-green, divided 

 into low irregular tubercles, these somewhat flattened and pointed; spines usually i to 3, sometimes 

 wanting, subulate, rigid, 2 cm. long, brown, spreading; flowers 6 cm. broad; inner perianth-segments 

 rose-purple to pinkish, narrow, acute; scales on ovary and flower- tube acute. 



Type locality: Not cited. 

 Distribution: Mexico. 



This plant is evidently related to Thelocactus lophothele. 



Illustrations: Mollers Deutsche Gart. Zeit. 25: 474. f. 6, No. 24; Bliihende Kakteen 

 3: pi. 130, as Echinocactus phymatothelos. 



Text-figure 5 is reproduced from the second illustration above cited. 



5. Thelocactus buekii (Klein). 



Echinocactus buekii] Klein, Gartenflora 8: 257. 1859. 



Stems simple, deep green; tubercles distinct, somewhat pointed, angled; spines about 7, red- 

 dish, unequal, some of them outwardly curved, the longer ones much elongated; flowers dark red; 

 inner perianth-segments narrow. 



Type locality: Mexico. 



Distribution: Known only from the type locality. 



Schumann refers this species to Echinocactus tulensis, but it is clearly different from 

 his illustration of that species. Its relationship must be rather with Thelocactus rinconensis 

 (see Schumann's figure. No. 75). 



This plant is probably named for Dr. Johannes Nicolaus Biick, a botanist and physi- 

 cian of Frankfurt, Germany, and author of the Index to De Candolle's Prodromus. 



Illustration: Gartenflora 8: pi. 266, as Echinocactus buekii. 



Text-figure 6 is reproduced from the illustration cited above. 



6. Thelocactus leucacanthus (Zuccarini). 



Echinocactus leucacanthus Zuccarini in Pfeiffer, Enum. Cact. 66. 1837. 

 Cereus tuberosus Pfeiffer, Enum. Cact. 102. 1837. 

 Cereus maelenii Pfeiffer, AUg. Gartenz. 5: 378. 1837. 

 Echinocactus porrectus Lemaire, Cact. Aliq. Nov. 17. 1838. 

 Echinocactus subporrectus Lemaire, Cact. Aliq. Nov. 25. 1838. 

 Echinocactus maelenii X Salm-Dyck, Cact. Hort. Dyck. 1842. 18. 1843. 

 Mammillaria maelenii Salm-Dyck, Cact. Hort. Dyck. 1844. 14. 1845. 

 Echinocactus leucacanthus tuberosus Forster, Handb. Cact. 287. 1846. 

 Echinocactus leucacanthus crassior Salm-Dyck, Cact. Hort. Dyck. 1849. 35. 1850. 

 Echinocactus theloideus Salm-Dyck, Allg. Gartenz. 18: 396. 1850. 



* This is the original spelling of the name, but it is sometimes written Echinocactus phymatothele, the ending 

 being the usual one for specific names of this kind. 



t The original spelling of this name was buekii, but on the accompanying plate it was buekii. 

 X This name is spelled macleanii by Hemsley (Biol. Centr. Amer. Bot. i : 534. 1880). 



