tridactyle, [506], [509], [510];

gemmiform, [506], [509], [510];

trifoliate, [508], [509], [510];

ophicephalous, [508], [509], [510];

function of, [508] f.;

of Endocyclica, [532];

of Cidaridae, [532];

of Echinothuriidae, [532], [535];

of Centrostephanus longispinosus, [532];

of Echinarachnius parma, [544], [545];