NOSE. 399 



The nerves of the nasal mucosa consist of groups of non-medullated 

 olfactory fibers, which unite in larger bundles in the tunica propria and pass 

 through the lamina cribrosa of the ethmoid to enter the olfactory bulb. 

 They are covered by prolongations of the dura. Medullated branches of 

 the trigeminal nerve occur both in the olfactory and respiratory mucosa. 

 After losing their ravelin they form terminal ramifications in the tunica 

 propria and may ascend into the epithelium. Thus they differ from the 

 olfactory fibers which generally do not branch. 



The arteries are found in the deeper layers of the tunica propria, 

 and they form a thick capillary network just beneath the epithelium. The 

 veins are very numerous, especially at the inner end of the inferior concha 

 where the tunica propria resembles cavernous tissue. Lymphatic vessels 

 form a coarse meshed network in the deeper connective tissue. Injec- 

 tions of the subarachnoid space follow the perineural sheaths of the 

 olfactory nerves into the nasal mucosa. 



