XVII. 

 THE NERVOUS SYSTEM. 



The Spinal Cord. 

 A. The Gross Structure of the Spinal Cord. 



Material. The spinal cord of a calf or some large animal. This 

 may be easily obtained at the large markets. It is only necessary 

 to ask the butcher to save, when he cuts the animal for the market, 

 the long spinal cord that is inside the backbone. 



Study the entire cord or a long piece of it. 

 Notice : 



a. The general shape, its length and diameter. Locate 

 the cervical and lumbar swellings in the regions of the 

 neck and the lawer part of the back. What causes 

 them? 



b. The roots, or attachments, of the spinal nerves. 



1. How are they arranged ? 



2. How near together are they ? 



c. Sketch. 



B. The Microscopical Structure of the Spinal Cord. 



Material. A microscopical slide showing a cross-section of a 

 spinal cord. 



Apparatus. A magnifying glass. A compound microscope. 



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