Figure 8 in Hybridization in the evolution of animal form and life-cycle

Figure 8. Larvae of an enteropneust hemichordate and echinoderms. A, tornaria larva of an acorn-worm (Enteropneusta); B, auricularia larva of a sea-cucumber (Holothuromorpha); C, bipinnaria larva of a starfish (Asteromorpha); D, echinopluteus larva of a sea-urchin (Echinomorpha); E, ophiopluteus larva of a brittle-star (Ophiuromorpha); F, doliolaria larva of a sea-lily (Crinomorpha). Scale bar = ∼1 mm (Adapted from Williamson, 1992, 2003.)