420 



SPECIAL HISTOLOGY. 



(0-008 — 0-012"') than the glandular canals and ascend, always 

 lined by rounded larger cells, straight through the epithelium, 

 in order to terminate on the surface with rounded orifices, 

 O'Ol'" in diameter, surrounded by a few large cells. The 

 tissue beyond these glands is, as in other regions, soft con- 

 nective tissue, without elastic elements. 



The mucous membrane, in the proper nasal cavities, is 

 very richly supplied with vessels, and less so in the accessory 

 sinuses. The terminal branches of these vessels form loose 

 plexuses around the glands, and in the trunks and branches of 

 the olfactory nerves; while on the surface of the mucous 

 membrane itself, they constitute a more close network with 

 numerous horizontal loops, at first sight leading to the sup- 

 position of the presence of papillce, which, however, do not 

 exist. The branches, also, of the arteries and veins enter into 

 numerous anastomoses, and constitute (the latter especially) 

 on the inferior spongy bones, the abundant spongiform plexus 

 already noticed. Nothing is known of the lymphatics of the 

 nasal mucous membrane. The nerves are, in the first place, 

 branches of the fifth pair (ethmoidal, posterior nasal, and a 

 branch of the greater anterior dental nerve), which supply 



Fig. 313. 



especially the ciliated region of the organ, presenting there the 

 same conditions as the nerves in other sentient mucous mem- 

 branes (of the pharynx for example), but also extend to the proper 

 olfactory region ; and, as I noticed in one instance in the 



Fig. 313. From the olfactory nerve of Man, x 350 diam.: A, nerve-tubes from 

 the Iractus, in water; B, in syrup, appearing contracted; C, nerve-cells, from the 

 bulb f D } nerve-fibres, from the branches in the olfactory organ. 



