Melocactus (Melon cactus) is genus of cactus with about 40 species. They are native to the Caribbean, northern South America, with some species along the Andes down to southern Peru, and a concentration of species in northeastern Brazil.
The genus Cactus Britton & Rose has been brought into synonymy with this genus.
Mature plants are easily recognizable by their cephalium, a wool- and bristle-coated structure at the apex of the plant, from which the inconspicuous flowers grow.
Source: Wikispecies , Wikipedoa : All text is available under the terms of the GNU Free Documentation License