98 



PHYSIOLOGY OF FARM ANIMALS 



[CH, 



third membrane called the arachnoid membrane. All these 

 membranes are composed of connective tissue. 



Both brain and spinal cord contain grey matter and white 

 matter. The grey matter consists of nerve cells together with 

 their smaller processes and a framework of supporting cells called 

 neuroglia. The white matter consists entirely of nerve fibres 



i4 



^Dendrons 





^Axon 



-Tx. 



Dendrons- vV /^ 



■Axon 



Fig. 46. Nerve cells from spinal cord of ox. 



representing axons of cells in the grey matter and tending to 

 run in parallel strands along the length of the cord. It is soft 

 and pulpy and contains very little connective tissue. 



The Brain. The different parts of the brain are described in 

 every text-book on anatomy, and it will suffice here to give a 

 very brief description of the principal of these parts with some 

 reference to their more important functions. 



