STRUCTURE OF THE NERVOUS SYSTEM 303 



8. With a pair of bone forceps, or nippers, break away the skull 

 until the entire brain' can be removed from the cavity. Examine the 

 different divisions, noting the relative position and size of the parts. 



9. With a sharp knife cut sections through the different parts, show- 

 ing the positions of the " gray matter " and of the " white matter." 



NOTE. If the entire class is to examine one specimen, it is gen- 

 erally better to have the dissecting done beforehand and the parts sep- 

 arated and tacked to small boards. This will permit of individual 

 examination. Sketches of the sciatic nerve, brachial plexus, and of 

 sections through the brain and spinal cord should be made. 



Location of Nerves in the Body. Several of the nerves of the body 

 lie sufficiently near the surface to be located by pressure and are easily 

 recognized as sensitive cords. Slight pressure from the fingers reveals 

 the presence of nerves in the grooves of the elbow (the crazy bone), 

 between the muscles on the inner side of the arm near the shoulder, 

 and in the hollow part of the leg back of the knee. These are all large 

 nerves. Small nerves may be located in the same manner in the face 

 and neck. 



