Animals without bones....

[Jac]

How many and what types of animals have no skeleton?

[incitatus]

How many is almost impossible to answer...certainly many thousands of species... All invertebrates, so insects, arachnids, arthropods in general, molluscs, sponges, jellyfish, sea anemones etc, in fact all radiates (animals with radial symmetry), gastropods, lamellibranchs....basically they outnumber vertebrates by about ten to one at a conservative estimate.