From the Greek koryphe, top, anthas, a flower, since theappear from the top of the plant (Cactaceae). Greenhouse cacti, first introduced into this country in the seventeenth century, which can be identified by the stout spines usually in a group on an areole and shaped like a spider.
C. andreae, large yellow flowers. C. asterias, globular to columnar, flowers pinkish-white. C. bu mamma, thick tubercles, yellow flowers. C. clava, taller growing, with yellow flowers. C. elephantidens, very thick, short tubercles, flowers large, pinkish-red. All from Mexico.
Pot every three years in a regular potting compost, with a sixth part added of sharp sand, grit and broken brick. Position in full sun on a shelf in the greenhouse, give air on all suitable occasions, water March to September and spray in the evening after a hot day. Some types with tap roots require very deep pots. They are not as free flowering as many cacti.