The former is closely applied to the ectoderm, forming with it the somatopleure or body-wall.
This second fold gives rise to the amnion, and is limited entirely to the somatopleure.
The part of the somatopleure, which grows round it, is to be regarded as a modified portion of the ventral wall of the body.
The mesoblast of the somatopleure is continued into the opaque area as a single layer of spindle-shaped cells.
At the junction of somatopleure and splanchnopleure they are more rounded than elsewhere.
somatopleure so·mat·o·pleure (sō-māt'ə-plur', sō'mə-tə-)
A complex sheet of embryonic cells formed by association of part of the mesoderm with the ectoderm and developing as the internal body wall.