Transverse section of a rat embryo. Showing relation of the paraxial mesoderm of the head to the lateral plates, the commencement of the formation of the otic vesicles and hyomandibular clefts, and the relation of the primitive heart to the pericardium and foregut. Labels: EC., ectoderm; SoM., somatic mesoderm; SpM., splanchnic mesoderm.

Transverse Section of a Rat Embryo

Transverse section of a rat embryo. Showing relation of the paraxial mesoderm of the head to the lateral…