Caption

Scanning electron microscope image of Lytechinus pictus [sea urchin] embryo at the 16-cell stage.The four large macromeres are behind the four small micromeres. The eight mesomeres are behind the macromeres. Remnants of the fertilization envelope can be seen attached to some of the cells.

Class Echinoidea

Superorder Echinacea

OrderTemnopleuroida

Lytechinus pictus

JEOL 35C SEM

Writer

Evelyn Spiegel, Louisa Howard

Keywords

marine invertebrate, SEM, sea urchin, embryo