The resulting cavity between the somatopleure and splanchnopleure is called the intraembryonic coelom.
This space will give rise to the thoracic and abdominal cavities.
The coelomic spaces in the lateral mesoderm and cardiogenic area are isolated.
The isolated coelom begins to organize into a horseshoe shape.
The spaces soon join together and form a single horseshoe-shaped cavity: the intraembryonic coelom.