Blood islands

Blood island of the umbilical vesicle
Time-lapse movie of blood islands in a chick embryo. The large green fluorescently highlighted clusters are blood islands.
Details
Carnegie stage6a
Days21
PrecursorMesoderm
Identifiers
LatinInsula sanguinea vesiculae umbilicalis
TEislands_by_E5.11.2.0.0.0.4 E5.11.2.0.0.0.4
Anatomical terminology

Blood islands are structures around the developing embryo which lead to many different parts of the circulatory system. Blood islands arise external to the developing embryo on the umbilical vesicle, allantois, connecting stalk and chorion. They are also known as Pander's islands or Wolff's islands, after Heinz Christian Pander or Caspar Friedrich Wolff.