Tentacles can refer to the elongated flexible organs that are present in some animals, especially invertebrates, and sometimes to the hairs of the leaves of some insectivorous plants. Usually, they are used for feeding, feeling and grasping. Anatomically, they work like other muscular hydrostats. Tentacles in invertebrates The phylum Mollusca includes many species with muscular hydrostats in the form of tentacles and arms. Octopus tentacles are usually called arms a type of short Tentacles with… (More on Tentacles)