_ r 



(f J Posterior Root Ganglion Stained in Osmic Acid. 



The posterior root ganglion of a small mammal was hardened 

 in llenirum's solution, embedded in paraffin, and sectioned longi- 

 tudinally. Fix the section to the slide, and mount in balsam. 



Study under low power. Observe that the fibrous cap- 

 sule around the ganglion is continuous with the epineurium 

 of the in-coming and out-going nerve trunk. The nerve 

 fibres are stained black. The nerve trunk breaks up into 

 several smaller bundles after it enters the ganglion. Be- 

 tween these bundles may be seen groups of ganglion cells, 

 round or oval in shape, with prominent nuclei and nucleoli. 

 They are stained a faint brown color. The cells are sur- 

 rounded by a nucleated capsule. Sketch the ganglion 

 under low power. 



(g) Postarior Root GFinglion Stained in Hsema- 

 toxylin. 



The posterior root iranglion of a dog was hardened in mercuric 

 chloride, stained in Delafield's hsematoxylin, embedded in paraffin, 

 and sectioned longitudinally. Fix to the slide, and mount in balsam. 



Study first under low power, and observe the structure 

 as described for (f) of this lesson. Sketch a number of 

 the cells with the intervening nerve fibres as seen under 

 high power. 



DRAWINGS FOR LESSON XIV. 



