196 



THE CACTACEAE. 



Echinocactus ottonis paraguayensis Heese, Gartenwelt 9: 266. 1905. 



Echinocactus ottonis uruguayus Arechavaleta, Anal. Mus. Nac. Montevideo 5: 213. 1905. 



Echinocactus arechavaletai Spegazzini, Anal. Mus. Nae. Buenos Aires III. 4: 496. 1905. 



Echinocactus spegazzinii Gurke, Monatsschr. Kakteenk. 15: no. 1905. 



Echinocactus ottonis brasiliensis Haage jr., Monatsschr. Kakteenk. 24: 41. 1914. 



Simple or cespitose, globular or somewhat depressed, more or less glossy green, 5 to 6 cm. in 

 diameter; ribs 10, broad and rounded below; areoles few, usually distant, 1 em. apart or more, small, 

 circular; spines acicular, brown, 1 cm. long or less; flowers from the uppermost areoles, one or more 

 appearing at a time, 5 to 6 cm. long, bright yellow; perianth-segments linear-oblong, acute; sta- 

 mens about half the length of the perianth-segments; style yellow; stigma-lobes red; axils of scales 

 filled with long brown wool and brown bristles. 



Typelocality: Supposed to be Mexico, but the species was described from a garden plant. 



Distribution: Southern Brazil, Uruguay, and adjacent parts of Argentina. 



The varietal name, Echinocactus ottonis paraguayensis, is usually credited to .Schumann 

 who used it in 1900 (Monatsschr. Kakteenk. 10: 179). The name Cereus ottonis appears 



in Pfeiffer's Enumeratio (47. 1837) as a syn- 

 onym of Echinocactus ottonis, but it does not 

 occur thus where Pfeiffer cites it (Nov. Act. Nat. 

 Cur. 16: 316. 1828), but as Cactus (Cereus) 

 ottonis. 



The following varieties are sometimes met 

 with: E. ottonis brasiliensis (Monatsschr. Kak- 

 teenk. 18: 48. 1908), pfeifferi Monville (Salm- 



FiGS. 2 10 and 211. Malacocarpus ottonis. 



Dyck, Cact. Hort. Dyck. 1844. 19. 1845), and minor (Forster, Handb. Cact. 302. 1846), 

 and Echinocactus muricatus hortatani (Labouret, Monogr. Cact. 232. 1853). 



A hybrid has been produced with this species and a plant called Echinopsis zuccarinii. 



Illustrations: Cact. Journ. 1: 43, 54; Monatsschr. Kakteenk. 12: 158; 29: 125; Martius, 

 Fl. Bras. 4 2 : pi. 51, f. 3; Edwards's Bot. Reg. 24: pi. 42; Rev. Hort. 1861: 270. f. 62; Curtis's 

 Bot. Mag. 58: pi. 3107; Link and Otto, Icon. Pi. Rar. pi. 16; De Laet, Cat. Gen. f. 11; 

 Mollers Deutsche Gart. Zeit. 25: 474. f. 6, No. 17; Riimpler, Sukkulenten 179. f. 98, as 

 Echinocactus ottonis; Anal. Mus. Nac. Montevideo 5: pi. 12; De Laet, Cat. Gen. f. 4; Tri- 

 bune Hort. 4: pi. 140, as Echinocactus ottonis tenuispinus; Link and Otto, Icon. PI. Rar. 

 pi. 15, as E. tortuosus; Nov. Act. Nat. Cur. 16: pl. 15, as Cactus ottonis; Verh. Ver. Beford. 

 3: pl. 19, f. 1, 2, as Melocactus tenuispinus; Anal. Mus. Nac. Montevideo 5: pl. 13, as E. 

 ottonis uruguayus; Gartenwelt 9: 267 ; Schelle, Handb. Kakteenk. 182. f. 116, as Echinocactus 

 ottonis paraguayensis; Anal. Mus. Nac. Montevideo 5: pl. 11, as Echinocactus arechavaletai; 

 Curtis's Bot. Mag. 68: pl. 3963, as Echinocactus tenuispinus; Diet. Hort. Bois 465. f. 323, 

 as Echinocactus tenuispinus ottonis; Karsten, Deutsche Fl. 887. f. 501, No. 12 ; ed. 2. 2 : 456. 

 f, 605, No. 12, as Echinocactus tenuissimus. 



