396 THE NASAL REGION IN EUTAENIA. 



with their situation, oftenest of small spherical form and granular 

 contents. 



The olfactory portion of the wall of the cavity may be divided for 

 the purpose of description as follows : 



(a) The mucous stratum, lying adjacent to the cartilaginous plate ; 

 it is constituted of large pigment cells, nerve fibres and capillaries, 

 forming a plexus, which surrounds the branch tiibules of Bowman's 

 glands. 



(/?) The sensory stratum, resting on a, which is composed mainly 

 of the nuclear portions of the sensory cells, arranged in 8-10 layers. 

 The central processes of these are much more delicate than the 

 peripheral, and in many places in my preparations are seen to ba 

 continuous with olfactory nerve fibres. The peripheral processes 

 exhibit a marked wavy contour, and in specimens, subjected to the 

 action of Muller's Fluid, appear possessed of granular contents. 

 Outside and beyond the cells of y, these abruptly become slender, 

 forming the so called sense hairs, (the Riechharchen of Max Schultze) 

 directed into the nasal cavity. These, when examined in salt solu- 

 tion, exhibit considerable movement, their axes becoming every now 

 and then wavy. At their origins are to be observed delicate swellings. 

 The nucleus of the sensory cell is perfectly spherical, and, like the 

 protoplasm surrounding it slightly glanular. 



(7) The superficial stratum, composed of cylindrical epithelium 

 cells with oval nuclei lying between the peripheral processes of /3. 

 The central ends of these are very delicate, and are not branched. I 

 have not observed any longitudinal striation on their surface. Form- 

 ing the outer terminations of these cells and encasing the delicate 

 swellings of the sense hairs, is seen, with favorable light, a distinct 

 border structure, corresponding to a membrana limitans olfactoria. 

 Through this the protoplasm of the cylindrical cells sends out exces- 

 sively fine cilia which are seen in their entirety in salt solution, but 

 when macerated, too often form only a granular precipitate at the 

 border of the cell. They do not reach nearly the same length as the 

 sense hairs, and exhibit a very slow movement, their axes remain- 

 ing perfectly straight all the while. Sometimes these are obscured 

 by the mucous and mucous cells from the adjacent glands. 



At the junction of the olfactory with the mucous portion of the 

 nasal wall a great development of Bowman's Glands is to be observed ; 

 their size here is extraordinary compared with those of other portions. 

 They are composed of cells of two forms, those in the depth of the 

 gland being large and almost spherical. As they approach the aperture 

 of the gland they gradually become smaller, assuming a rhombohedral 

 form. The large cells in ordinary stained preparations do not show 



