Mammillaria is one of the larger genera in the Cactus family, and one of the most variable.

No Holiday Potluck, so send in photos.

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Ferocactus are fierce cacti from Mexico and Southern USA. Leuchtenbergia consists of a single species, from Mexico.

Echinopsis now includes Lobivia, Tricocereus, Helianthrocereus, and Pseudolobivia.

Your favorite cactus, nicely staged.

Epiphytic cacti do not live in soil like other cacti but in places like rain forests they inhabit the forks or large branches of trees, their roots clinging tightly to their host. Epiphytes have specially designed stomata (leaf openings), that help absorb moisture from the open air.

The three most common types of mutation are crests, monstrose growth and variegation. All of these are mutations of the cellular structure.