[Peculiarities of myelin formation in the spinal roots of the rabbit].

The axon sheath formation in the ventral and dorsal spinal roots of newborn rabbits is discussed. The mesaxon grows at a greater rate than the outer plasmalemma of the Schwann cell, thereby giving rise to folds in the mesaxon. The compact myelin spiral is formed by the apposition of 2-3 lamellae.