"Ovum of a Sea-Urchin, showing the radially striated cell-membrane, the protoplasm, containing yolk-granules, the large nucleus (germinal vescicle), with its network of chromatin and a large nucleolus (germinal spot)." -Parker, 1900

Sea Urchin Ovum

"Ovum of a Sea-Urchin, showing the radially striated cell-membrane, the protoplasm, containing yolk-granules,…