Cephalium is a frequently brightly coloured structure of wool and bristle at the growing tip of certain cacti. It is most commonly found on cacti of the genus Melocactus and can take a number of colours, forms and shapes. The cephalium will only begin growing after a cactus has reached a certain size or age. Once flowering begins the flower buds will form from the cephalium.

• Flowers emerge from cephalium of Arrojadoa penicillata.
• Cephalium of Melocactus matanzanus
• Lateral cephalium of Espostoa lanata