114 



NERVOUS SYSTEM OF VERTEBRATES. 



In man the cutaneous fibers in the cranial nerves (trigeminus 

 and vagus) form a longitudinal tract in the medulla oblongata 

 which corresponds to the dorsal tracts of the spinal cord and 

 continues caudally to the level of the first cervical nerve, the tr actus 



Fig. 56. — Transverse section through the spinal V tract and the substance of 

 Rolando of a new-born rabbit. From Cajal (Beitrage u. s. w.). A, ventral part of 

 the root; a, interstitial cell; c, border cell; d, cell-islands of the substantia gelati- 

 nosa; e, small/cells of the islands; /, stellate cells not arranged in islands; g, cells 

 between islands; h, a cell whose neurite seems to go into the white substance or 

 toward the root. 



