FRAILEA. 
209 
Key to Species. 
Stems cylindric, usually simple. 
Stems globular, more or less cespitose. 
Seeds puberulent. 
Seeds smooth. 
Ribs more distinct than in the other species. 
Ribs very indistinct. 
Radial spines 12 to 14. 
Radial spines 5 to 9. 
Plants usually simple; fruit red. 
Plants cespitose; fruit black. 
Uncertain relationship. 
1 . Frailea gracillima (Lemaire). 
1. F. gracillima 
2. F. grahliana 
3. F. pumila 
4. F. schilinzkyana 
5. F. cataphracta 
6. F. pygmaea 
7. F. caespitosa 
,8. F. knippeliana 
Echinocactus gracillimus Monville in Lemaire, Cact. Gen. Nov. Sp. 24. 1839. 
Echinocactus pumilus gracillimus Schumann, Gesamtb. Kakteen 394. 1898. 
Cylindric, simple, 10 cm. high, 2.5 cm. in diameter, grayish green; ribs about 13, but indistinct, 
more or less spiraled, tuberculate; areoles small, with a purple blotch beneath each one; radial spines 
about 16, setaceous, white, 2 mm. long, more or less appressed; central spines 2 to 4, more or less 
unequal, 4 to 8 mm. long; flowers yellow, 3 cm. long; scales on the ovary and flower-tube woolly and 
bristly in their axils; fruit 6 mm. in diameter; seeds 1.5 mm. long. 
Type locality: Not cited. 
Distribution: Paraguay. 
Echinocactus gracilis (Forster, Handb. Cact. 304. 1846) is given as a synonym of this 
species, but was not described. This is probably the E. gracilis Lemaire of collections 
(Monatsschr. Kakteenk. 10: 16. 1900). 
Illustration: Monatsschr. Kakteenk. 9: 55, A, as Echinocactus gracillimus. 
2 . Frailea grahliana (Haage jr.). 
Echinocactus grahlianus Haage jr. in Schumann, Monatsschr. Kakteenk. 9: 54. 1899. 
Cactus grahlianus Kuntze, Deutsch. Bot. Monatsschr. 21: 193. 1903. 
Cespitose; plants small, depressed-globose, 3 to 4 cm. in diameter; ribs about 13, low and indis¬ 
tinct; spines all radial, 9 or 10, subulate, appressed, somewhat curved backward, 3.5 mm. long; 
flowers 4 cm. long, yellowish; fruit 6 mm. in diameter; seeds brown, puberulent. 
Type locality: Paraguari, Paraguay. 
Distribution: Paraguay; also Argentina, ac¬ 
cording to Spegazzini. 
Echinocactus grahilianus adustior (Monats¬ 
schr. Kakteenk. 14:156. 1904) is only mentioned. 
Illustrations: Schumann, Gesamtb. Kakteen 
Nachtr. f. 20; Monatsschr. Kakteenk. 9: 55, B; 
12: 141, as Echinocactus grahlianus. 
3 . Frailea pumila (Lemaire). 
Echinocactus pumilus Lemaire, Cact. Aliq. Nov. 
21. 1838. 
Plant cespitose, small, globose, umbilicate at 
apex, deep green, sometimes becoming reddish; ribs 
13 to 15, more distinct than in the related species, 
more or less tuberculate; areoles small, nearly cir¬ 
cular; spines all pubescent, yellowish brown; radial 
spines 9 to 14, setaceous, more or less appressed; 
central spines 1 or 2, flower 2 cm. long, yellow; axils of 
scales on the ovary and flower-tube woolly and setose; seeds smooth, brown, obovate, 1.5 mm. long, 
angled on the back; depressed hilum much smaller than in Frailea cataphracta. 
Type locality: Not cited. 
Distribution: Paraguay and Argentina. 
