[Morphogenesis of the cerebral fissures in sheep]

The author studies the development and formation of the boundary fissures in the brains of the foetuses of sheep during their embryonal development from a vertex-to-coccyx length (VC length) of 38 mm (39th to 40th day) to birth. The marginal fissures of the cerebral hemispheres were found to develop first. The sulcus hippocami develops from them at a VC length of 46 to 48 mm (42nd to 45th day) and is one of the fissures with a constant course of formation. Sulcus rhinalis lateralis develops from a VC length of 70 to 72 mm (49th to 50th day). The caudal part of this fissure is deeper during the whole prenatal development than the rostral part.