2IO THE CACTACEAE. 



This species, the first of the group to be described, is not even now very well understood. 

 The description of the seeds given above is drawn from Dr. Shafer's plant from Concordia, 

 Argentina (No. 125); he notes that it grows in gravel and, being inconspicuous, is hard 

 to find. 



In 1920 Dr. C. Fiebrig, Director of the Botanical Garden at Asuncion, Paraguay, 

 sent us a fine specimen; it is very cespitose, with 20 heads or more, forming alow mound 

 nearly 10 cm. in diameter. 



Illustrations: Knippel, Kakteen pi. 8; Monatsschr. Kakteenk. 9: 55, C, as Echino- 

 cactus pumilus. 



Figure 223 shows a potted plant sent by Dr. Fiebrig in 1920 (No. 7). 



4. Frailea schilinzkyana (Haage jr.). 



Echinocactus schilinzkyanus Haage jr. in Schumann, Monatsschr. Kakteenk. 7: 108. 1897. 

 Cactus schilinzkyanus Kuntze, Deutsch. Bot. Monatsschr. 21: 193. 1903. 



Simple or somewhat cespitose, usually globular, somewhat flattened above, about. 3 em. in 

 diameter, but umbilicate at apex; ribs 10 to 13, but very indistinct, more or less spiraled, strongly 

 tubereled; radial spines 12 to 14, 2 to 3 mm. long, more or less appressed and reflexed; central spine 

 solitary, stouter than the radials; flowers small, often cleistogamous ; fruit yellowish. 



Type locality: Meadows near the River Paraguari, Paraguay. 



Distribution: Paraguay; also Argentina, according to Spegazzini. 



Nicholson (Diet. Gard. Suppl. 336. 1900) states that "this may be a Mammillaria." 



Echinocactus schilinzkyanus grandiflorus Haage jr. (Monatsschr. Kakteenk. 8: 143. 

 1898) is only mentioned. 



Illustrations: Cact. Journ. 1: 45; Schelle, Handb. Kakteenk. 183. f. 117; Schumann, 

 Gesamtb. Kakteen Nachtr. f. 21 ; Monatsschr. Kakteenk. 9: 55, D, as Echinocactus schilinz- 

 kyanus. 



5. Frailea cataphracta (Dams). 



Echinocactus cataphractus Dams, Monatsschr. Kakteenk. 14: 172. 1904. 



Small, globose plants, 1 to 2 em. in diameter, deeply umbilicate at apex, simple or sometimes pro- 

 liferous, dull green ; ribs low and broad, 10 to 15 ; tubercles flattened above, each with a purple lunate 

 band near the margin; radial spines 5 to 9, straight, 1 to 2 mm. long, appressed, yellowish or white; 

 central spines none; flowers evidently minute, but unknown; fruit small; seeds comparatively large, 

 2 mm. broad. 



Type locality: Described from greenhouse plants. Supposed to have come from Para- 

 guay. 



Distribution: Paraguay. 



Seeds planted November 24, 1912, developed into plants which flowered in March 

 1 91 5. In the case of a plant which fruited in 1914 the seeds were carried away by ants 

 and were found germinating in the sand in March 191 5. 



6. Frailea pygmaea (Spegazzini) . 



Echinocactus pygmaeus Spegazzini, Anal. Mus. Nac. Buenos Aires III. 4: 497. 1905. 



Simple or cespitose, half buried in the ground, globose, umbilicate at apex, with a turbinate base, 

 1 to 3 em. in diameter, dull green; ribs 13 to 21, obtuse, low, divided by transverse depressions into 

 tubercles; spines 6 to 9, white, setaceous, 1 to 4 mm. long, appressed; flowers from the apex of the 

 plant, often cleistogamous, with dense, rose-colored pubescence without, 2 to 2.5 cm. long; inner 

 perianth-segments lanceolate, acute, yellow; filaments and style white; stigma-lobes yellowish; 

 seeds 2 mm. long, black, shining, with a large oblong hilum nearly as long as the body. 



Type locality: Mountains about Montevideo, Uruguay. 

 Distribution: Uruguay and province of Entre Rios, Argentina. 



Echinocactus pygmaeus phaeodiscus (Spegazzini, Anal. Mus. Nac. Buenos Aires III. 4: 

 498. 1905) is similar to the type, but has lower ribs, blackish areoles, and 6 to 12 



