Before revision: In some species the migration from neural crest comes in two waves, with the first giving birth to the corneal epithelium and the second invading the epithelium-secreted stromal anlage devoid of cells; in other species both populations come from a single wave of migration.
After revision: In some species the migration from neural crest comes in two waves, with the first giving birth to the corneal endothelium and the second invading the epithelium-secreted stromal anlage devoid of cells; in other species both populations come from a single wave of migration.