MALACOCARPUS. 187 
Pa lustrations: Schelle, Handb. Kakteenk. 147. f. 73; Engler and Drude Veg. Erde 8: pl 
5, f. 30; Schumann, Gesamtb. Kakteen f. 53, as Echinocactus ceratites; Cact. Mex Bound 
pl. 33, f. 7, as Echinocactus sandillon. . ) ) 
igure 197 is from a photograph of a plant in t i i i 
taken by MieyN Roc in P plant in the Botanical Garden at Santiago, Chile, 
\8 t) 23. MALACOCARPUS Salm-Dyck, Cact. Hort. Dyck. 1849. 24. 1850. 
_ Plants globose to short-cylindric, either simple or clustered; ribs definite i i 
entire or broken up into more or less definite tubercles; areoles felted, copecially whea yor 5 nine 
caning: flowers from the center of the plant, broad and short, mostly yellow; perianth funnelform to 
wu rotate; stigma-lobes in typical species red; ovary densely covered with scales bearing an abun- 
ance of wool and usually bristles in their axils; fruit soft, rose-red or crimson; seeds brown or 
black, tuberculate with a broad truncate base; hilum white. 
Prince Salm-Dyck, who established the genus, assigned 6 species of Echinocactus to 
“ of which FE. corynodes Pfeiffer was the first and is therefore taken by us as the generic 
ype. 
Schumann treats the group as a subgenus of Echinocactus; he assigns 3 species to it, 
all from the State of Rio Grande do Sul, Brazil; Arechavaleta, who follows Schumann’s 
treatment, describes 6 species from Uruguay. Besides those heretofore treated in the 
subgenus Malacocarpus, we refer here most of the species assigned by Schumann to the 
subgenus Notocactus. 
We recognize 29 species, all from South America and all found south of the Equator. 
The generic name is from maakds soft, and xaprés fruit, referring to the fleshy fruit. 
Key To SPECIES. 
A. Plants globular to stout-cylindric. 
B. Areoles of the ovary and flower-tube long-hairy or long-woolly. 
C. Spines 4 cm. long or less, straight. 
D,. Flowers yellow. 
Ribs acute. 
Spines subulate.......... 000 cee ee eee e nent nen e reese sence reres 1, M. tephracanthus 
Spines acicular. 
Spines yellow. ..... 0.20: cece cece renee teen ener reser e ese e cece sense 2. M. schumannianus 
Spines white or becoming silvery. 
Spines 3 tO 7..... 0. cece cece rere reece een e recente ee se teases cece: 3. M. grossei 
Spines 9 OF 10...... 02sec ee eee eee teen een eee rete teense ese scc sys 4. M. nigrispinus 
Ribs obtuse or rounded. 
Ribs spirally arranged, broken into tubercles. 
Spirals many; plant gray.......-.. +. sees eee ee errr rere eres tence sete es Se M. reichei 
Spirals few; plant brown.......-..-.++eseere secret rere tress res ceeees 6. M. napinus 
Ribs straight or nearly so, undulate or continuous. 
Perianth short-funnelform. 
Perianth-tube very stout. ......... 5. see e ee ere ere t eter eer te ec crees 7. M. apricus 
Perianth-tube relatively slender. 
Plant deeply umbilicate; spines slender. .....2.00ececeeeeeeececess+ 8. M. concinnus 
Luce ce cece te ce cece eerenees 9. M. tabularis 
Plant slightly umbilicate; spines short 
Perianth campanulate to subrotate. 
Spines setaceous or acicular. 
Ribs 30 to 40; radial spines up to 40 Or mMore.... ++... +++ -eeeeereees 
Ribs 21 or fewer; radial spines much fewer than 40. 
Ribs very low and rounded. ......-..+++-.seerrecrrese reste sees 11. M. pulcherrimus 
Ribs prominent. 
Areoles only 4 to 7 mm. apart......-.-s+ es errr reer reese sense 
Areoles more separated. 
Inner perianth-segmen 
Inner perianth-segmen 
Spines stouter, subulate. 
Inner perianth-segments 2 to 3 cm. long. 
Spines terete. 
10. M. scopa 
12. M. muricatus 
M. linki 
ts obtuse or merely apiculate........... 13. i 
M. ottontis 
ts acute or acuminate.........-.+++++-+ 14. 
15. M. catamarcensis 
Spines slender, slightly curved. .....-+ ++ ++ ererrrer reer eres ees 
Spines stout, rigid. .....--.000cse eer se etre re esse sere se esses 16. M. patagonicus 
Spines flattened. ; 
17. M. erinaceus 
Central spines not much longer than the radials. ......-.+-+++++ 
