immediately_preceded_by developmental stage Medaka stage 27 Medaka stage 28 30 somite stage OlatDv:0000310 Onset of retinal pigmentation Zoological Science 11: 825-839 (1994) - 2 days 16 hrs Stage 28 (2 days 16 hrs) 30 somite stage (Onset of retinal pigmentation): The embryonic body with a caudal vein between the 10th and 22th somites encircles about 2/3 of the yolk sphere. Pigmentation advances around the retina, and several melanophores occupy the dorsal wall of the viscera beneath the 1st to the 5th somites. The bulge of the liver becomes definitive in the left side of the 3rd to 4th somites. The anlage of the pancreas appears as a ventral eminence on the right side beneath and slightly anterior to the 3rd somite. Three sinuous portions of the vitelline veins consisting of the left and right ducts of Cuvier and 4 sinuous portions of the vitello-caudal vein meander on the yolk sphere. The blood cells (8.7 m in diameter) flatten slightly. The posterior of the two otoliths in each otocyst is slightly larger than the anterior. - 2 days 16 hrs medaka_ontology