112 



HISTOLOGY. 



the cells of the second type a few sympathetic fibers are put in communi- 

 cation with a large number of T-cells. Apparently in mammals there are 

 no fibers which traverse the spinal ganglion without entering into relation 

 with its cell bodies. The observation that there are types of spinal ganglion 



Motor cell of 

 anterior horn (in 

 the spinal cord). 



Blood vessel. 



Dorsal ramus. 



Visceral ramus. 

 Cell of a sympathetic ganglion. 



FIG. 137. DIAGRAM OF THE NERVOUS ELEMENTS OF A SPINAL GANGLION, BASED UPON 



METHYLENE BLUE PREPARATIONS. 



The sensory fibers are represented by continuous lines, the sympathetic fibers by dotted lines, the motor 

 fibers by linear series of dashes. The medullary heaths of the motor fibers of thei_ ventral root 

 have not been drawn. . ( 



cells with processes confined within the ganglion, and that some of the cells 

 have non-medullated fibers, accords with the fact ascertained by counting, 

 that the ganglion may contain about six times as many cells as there 

 are medullated fibers in the dorsal root. 



Sympathetic ganglia consist of smaller cell bodies, often pigmented, 



