Professor Haeckel adduces the fossil Crossopodia and Phyllodocites as examples of the annelidan forms, by the coalescence of which the Echinoderms may have been produced; but, even supposing the resemblance of these worms to detached starfish arms to be perfect, it is possible that they may be the extreme term, and not the commencement, of Echinoderm development.
"Critiques and Addresses"
Thomas Henry Huxley