The genus includes 7 species. They are small, with globular or short cylindrical, well provided with spines and with low ribs. Echinomastus Macdozvellii. N. Mexico. A beautiful species with a pale green entirely covered with long white spines. Ribs number 20 to 25. The areoles are furnished with white wool; radial spines number 15 to 20, central spines 3 to 4. The are pink.
Echinomastus erectocentrus. The stem grows singly, and is bluish-green, with 20 or more ribs, arranged spirally. The grey-green areoles are set closely together; radial spines number about 16, andi there is only 1 central spine. Theare reddish-purple and formed at the top of the stem. A handsome species which grows easily from . The plants thrive well in full sunshine in a mixture of -mould, loam and chippings, in equal parts.