1. Leaf-cactus (Phyllocactus anguliger). 2. Stapelia (simulating a cactus). 3. A Cereus (Cereus dasycanthus). 4. Globe-cactus (Echinocactus horizonthalonius). 5. Wart-cactus (Mammilaria pectinata). 6. Hairy Opuntia (Opuntia filipendula)—a. the blossom, enlarged. 7. Melon-cactus (Melocactus communis). 8. Giant Cactus (Cereus giganteus)-a, blossom, enlarged; b fruit, enlarged. 9. Mexican Opuntia (Opuntia coccinellifera)-a, the fruit ("prickly pear"), enlarged.