If we examine the base of the brain, a number of nerves are seen to come off from its surface. They vary in size, as they do also in function, and among them are numbered the nerves of the special senses of smell, sight, taste, and hearing. The cranial nerves are arranged symmetrically on either side of the base of the brain, and for the most part distribute their branches to parts on the side from which they arise. There is a want of agreement in this country between human and veterinary anatomists as to the enumeration of the cranial nerves. By the one they are described as nine, by the other as twelve. We need not, however, enter into the pros and cons of this question here, but we give below the numerical designations of each: -
Olfactory Nerves ...
Pathetic Nerves ...
Trifacial or Lingual Nerves..
Facial Nerves (Portio dura)..
Auditory Nerves (Portio mollis) .....
Pneumogastric or Vagus Nerves ...
... 10 ..
Spinal Accessory Nerves ...