HEAD. 109 



guttural poncli, and receiving all the lympliatics of the 

 head ; 2 — Tlie submaxillary, situated in the intermax- 

 illary space, and receiving the lymphatics of the tongue, 

 cheeks, lips, nostrils and nasal fossae. 



IVEUROLOGY. 



Twelve pair of cranial nerves. 



1. Olfactory. — Formed by the olfactory lobe, 

 which has the appearance of a ganglion, grey inferiorly, 

 and white superiorly. It rises by two roots of white 

 substance, which unites into one band, and is situated 

 in the ethmoidal fossa, where through the foramina of 

 the cribriform plate of the ethmoid, it sends the true 

 nerves. The olfactory lobes are hollowed, and com- 

 municate with the cavity of the lateral ventricules. 

 The nerves, varying in number, ramify in the mu- 

 cous membrane of the septum nasi and ethmoidal vol- 

 utes. They are the special nerves of the organs of 

 smell. 



2. Optic. — E.ise on the external side of tlie thalami 

 optici by white bands, and from the corpora quadri- 

 gemina. Course : Pass in front of the cerebral pedun- 

 cles, arrive at the inferior face of the brain, form the 

 chiasma, reach the optic duct, and perforate the ocular 

 envelope at the bottom of the ocular globe, and enter 



