162 
THE CACTACEAE. 
Type locality: Near Paysandu, Uruguay. 
Distribution: Northwestern Uruguay. 
Illustration: Anal. Mus. Nac. Montevideo 5: pi. 15, as Echinocactus melanocarpus. 
Figure 171 is copied from the illustration of the type plant above cited. 
16 . Gymnocalycium Uruguayense (Arechavaleta). 
Echinocactus uruguayensis Arechavaleta, Anal. Mus. Nac. Montevideo 5: 218. 1905. 
Usually much depressed; ribs 12 to 14, strongly tubercled; areoles orbicular, grayish tomentose 
when young; spines 3, 1.5 to 2 cm. long, usually white; flowers 4 cm. long; inner perianth-segments 
linear- lanceolate. 
Type locality: Paso de los Toros, Uruguay. 
Distribution: Known only from the type locality. 
Illustration: Anal. Mus. Nae. Montevideo 5: pi. 14, as Echinocactus uruguayensis. 
Figure 172 is copied from the illustration of the type plant above cited. 
Fig. 173. —Gymnocalycium megalothelos. Fig. 174. —Gymnocalycium kurtzianum. 
17 . Gymnocalycium megalothelos (Sencke). 
Echinocactus megalothelos Sencke in Schumann, Gesamtb. Kakteen 415. 1898. 
Plant simple, somewhat depressed-globose, 10 cm. in diameter, but sometimes said to be short- 
columnar, in cultivation becoming bronzed; ribs 10 to 12, prominent, 10 to 12 mm. high, acute, 
deeply divided into tubercles; spines acicular, brownish; radial spines 7 or 8, spreading or sometimes 
ascending, 1 to 1.5 cm. long; central spine solitary, ascending or porrect, more or less curved, 2 to 3 
cm. long; flower campanulate-funnelform, erect, 3 to 4 cm. long; outer perianth-segments broad, 
greenish purple with a broad ovate acute tip; inner perianth-segments pinkish white; scales on the 
ovary very broad with a pinkish tip. 
Type locality: Paraguay. 
Distribution: Paraguay. 
This species was collected in Paraguay by Professor R. Chodat in 1915 and has flowered 
repeatedly in the New York Botanical Garden. 
Plate xviii, figure 1, shows the plant collected by Professor Chodat. Figure 173 is 
from a photograph of the same plant. 
