43 



75- Ulnar nerve. Transection. Hermann's 



fluid (§23); paraflin ; sections yu. Stain for 2-3 minutes with 



picrofuchsin. 



This will be a supplementary preparation to 74, since here 

 the myelin is not dissolved out and is stained black by the osmic 

 acid. Compare the two preparations, recognizing in this one the 

 features enumerated above. 



76. Vagus and sympathic. Transection ; Her- 

 mann's fluid (§ 23) ; paraffin. Stain 2-3 minutes with picro- 

 fuchsin. 



There will also be included a transection of the carotid artery. 

 Note the myelinic nerve fibers, with blackened myelinic sheaths in 

 both nerves and in the vagus, the variation in their caliber. In ad- 

 dition, recognize if possible the transected amyelinic fibers by the 

 absence of a myelinic sheath. 



GANGLIA. 



77. Sympathetic ganglion. Cat. Section of the semilunar 

 ganglion. Zenker's fluid ; paraffin ; sections fA.. Stain i 

 hour with hematoxylin, picrofuchsin 30 seconds. Observe well the 

 characteristic appearance of ganglion cells in section ; their finer 

 structure, indications of their processes ; recall the structure of the 

 nerve cells in 70 and 71, realizing the extent of the dendrites. 



78. Spinal ganglion. Section of the ganglion upon 

 the dorsal root of a spinal nerve. Flemming's fluid ; paraffin ; 

 sections fi. Stain with hematoxylin i hour, picrofuchsin 30 

 seconds. Observe the characteristic appearance of a ganglion, the 

 (apparently) round ganglion cells with their capsules ; the nerve 

 fibers ; the connective tissue within the ganglion and forming a 

 covering sheath. Compare with 77. What is the real form of the 

 nerve cells in the two kinds of ganglia and their relation to the 

 fibers ? 



PERIPHERAL NERVE ENDINGS. 



79. Motor end-plate. From the muscle. 

 Demonstration. The preparation will show the nerve fiber termin- 

 ating in the end-plate with its nuclei and the branching axis- 

 cylinder. 



