110 THE CACTACEAE. 
Schumann described the group briefly, as follows: 
“Ribs mostly moderately high, laterally compressed, almost like cardboard, very many (E. 
coptonogonus with only 13 to 15); flowers small, like a Mammillaria flower; ovary with scales and 
glabrous.” . 
KEY TO SPECIES. 
Ribs thick at base, triangular in cross-section. 
RibS 10 tO 14... ccc cee cee ee ee eee ee eee ee ee ee ee ee eee eee eee teens 1. E. coptonogonus 
Ribs about 35.0... 0.0 ce ccc ccc ce ce ee eee eee ee ee ee ee ee ee eben ee ee eben eee 2. E. hastatus 
Ribs always numerous, very thin even at base. 
Ribs 100 OF MOTE... 1... ee eee cee e ee ee ee eee e ee eeeeeee 3. E. multicostatus 
Ribs 25 to 55. 
Some or all of radial spines acicular or setaceous. 
Radial spines all acicular, white, straight. 
Flowers greenish yellow. ; 
Central spines terete... 0.0.0.0... c cece te tee tee ee see recees 4. E. wippermannii 
Central spines narrow, but flattened. ..............0..0000 000 cece cece eeeeees 5. E. heteracanthts 
Flowers not greenish yellow. 
Central spines 4.0.0... 0. cece cece ce ce ee teen ee eee eee seen eeeenes 6. E. albatus 
Central spines 3. 
Central spines annulate; apex of plant not depressed...................0-. 7. E. lloydit 
Central spines not annulate; apex of plant umbilicate...................... 8. E. zacatecasensis 
Upper radial spines subulate, some flattened. 
Spines yellow or white. 
Spines only 5 OF 6.2.0... 6.6 cee cece cece ee ee eee ee tte tees eeeeeee 9. E. lamellosus 
Spines 8 tO 11... ee cee ee te eee ete tebe ee eneeees 10. E. grandicornis 
Central and upper spines brownish............. 00.0... cece ccecececccececees 11. E. arrigens 
None of the spines acicular. 
Perianth-segments rather short. 
All spines appressed against plant. .............0.. 0... c cece cece cece ce eeeeues 12. E. violaciflorus 
Some spines erect or porrect. 
Ribs about 25. 
Four upper spines much elongated. ...........0.. 0... cccccuccuccceuecuue 13. E. obvallatus 
Spines all somewhat similar. 
Spines only 5............ 000. e cece ee eae Vege dete es becdes eatev ee eeg 14. E. pentacanthus 
_. Spimes 10 or more... 2... ce cece cece ec nceeenetevennnns 15. E. crispatus 
Ribs 30 or more. 
Radial spines white... 2.2.0... 0... ce ccc cece ence cc ceeeeeeeues 16. E. dichroacanthus 
Radial spines brown. 
Flowers purplish. .........0.00 0 ccc eee ec ce cece eee cccneeceeee 17. E. anfractuosus 
Flowers yellow. 
Upper and flattened spines 3, rather short, red....... 18. E. tricuspidatus 
. Upper and flattened spines usually 1, rarely 2............... 000-0000 19. E. phyllacanthus 
Perianth-segments much elongated and widely spreading or recurved .... 20. E. lanctfer 
Species not grouped .............. ccc cece cece eee eaee 21. E. gladiatus 
a d 22 E. confusus 
2 1. Echinofossulocactus coptonogonus (Lemaire) Lawrence in Loudon, Gard. Mag. 17:317. 1841. 
 Echinocactus coptonogonus Lemaire, Cact. Aliq. Nov. 23. 1838. 
Echinocactus coptonogonus major Lemaire, Cact. Gen. Nov. Sp. 87. 1839. 
Echinofossulocactus coptonogonus major Lawrence in Loudon, Gard. Mag. 17: 317. 1841. 
Simple or perhaps cespitose, globular or a little depressed, 7 to 10 cm. high, glaucous-green; ribs 
stout, 1.5 cm. high, 10 to 14, acute; areoles about 2 cm. apart, when young abundantly floccose, but in 
age naked; spines 3 to 5, stout, a little incurved, the longest 3 cm. long, flattened; flowers 3 cm. long, 
4 cm. broad; inner perianth-segments numerous, linear-oblong, acute, purple with white margins; 
ovary brownish violet, bearing thin scales. 
Type locality: Mexico. 
Distribution: Mexico, near San Luis Potosi and Pachuca, according to Schumann; the 
plant found at the latter locality is probably to be referred elsewhere. 
This species 1s very abundant about San Luis Potosi from which place we have received 
considerable material from Orcutt and Palmer. It does not do well in cultivation. Only 
one plant is now alive in our collection and this has never flowered. 
Echinocactus interruptus Scheidweiler (Cact. Hort. Dyck. 1849. 29. 1850) was referred 
here but never published. It was also used by Pfeiffer o- 
nym of E. exsculptus. y (Enum. Cact. 65. 1837) as a syn | 
