Even though the tentacles of an octopus may appear to have a bone or two, in reality, they don't.
Flatworms, a type of invertebrate animal, also don't have any bones.
Butterflies are delicate and soft insects that lack any piece of bone in their body.
Jellyfish are beautiful-looking creatures in the sea. They don't have bones in their body which are made up of mesoglea.
Squids have soft bodies with no bones for muscular support.
Sea cucumbers are marine animals with soft and flexible bodies that do not contain bones.
Even though there are hard spikes all over the body of sea urchins, they lack proper bone structure for support.
The bodies of slugs are soft and slimy without any bones.