- . - 



-"^ 'A' 

 ' . .. " /- 







FIG. 18. SPINAL NERVK 



Transverse section through the spinal cord 



of a 76-hour chick embryo showing 



early development of a 



spinal nerve. 



A, motor root; B, sensory root; C, bifurca- 

 tion of fibers of sensory root; a, b, c, d, neu- 

 rones in various stages of differentiation. 

 After Cajal. From Bailey and Miller, 



Embryology. 

 By permission of William Wood & Co. 



