'80 



SPECIAL HISTOLOGY. 



and the same may be said of it in the nasal fossoe themselves, particu- 

 larly in the glandular parts, notwithstanding the intimate connection of 

 the two. A remarkable appearance presented itself to me in the body 

 of a youth aged 15 (who, as I was informed by Virchow, also exhibited 

 ossifications in the lungs), consisting in the deposition — in the mucous 

 membrane, in all these accessory cavities, as well as in the similarly 

 constituted mucous membrane on the concave side of the spongy bones, 

 immediately beneath the epithelium — of calcareous salts, to such an ex- 

 tent, that its uppermost layer was transformed into a peculiar ossified 

 though still flexible membrane, in which there existed, in places, larger 

 and smaller, often very regularly disposed openings, but no evidence of 

 a special structure. Under this layer, which, where well developed, ap- 

 peared perfectly white, like a membrane filled wuth air-vesicles, as which 

 I at first regarded it, there always occurred a looser connective tissue 

 with vessels, of which latter, however, some were also incrusted ; and 

 in the deeper parts of the epithelial layer itself, there were scattered, 

 smaller, simple or aggregated concretions, like " brain-sand" in minia- 

 ture. 



The proper olfactory mucous memhrmie of all the divisions of the 

 organ, occupies only the uppermost parts of the septum and of the 



walls of the proper nasal /ossre, where 

 the superior spongy bones are situated, 

 to a distance of about |-1 inch down- 

 wards from the lamina crihrosa. It is 

 distinguishable, even by the naked 

 eye, from the contiguous ciliated mem- 

 brane, by its greater thickness and its 

 color, which is sometimes yellowish, as 

 in Man, the Sheep, and Calf; some- 

 times yellowish-brown or brown, as in 

 the Rabbit and Dog ; and, when ex- 

 amined microscopically, it is seen to 

 be bounded by a tolerably well-defined, 

 toothed or undulated border. The 

 differences of the structure depend 

 upon the condition of the epithelium, 

 the occurrence of numerous peculiarly 

 constructed glands, which I shall term 

 " Bowman's glands," and upon the relations of the nerves. The 



Fis 



312. 



^^ . ■, . r-,^=; ,,,.^,..-£.;^feri 



laMiit'iiij 



Fig. 312. — From the nasal mucous membrane of the Slieep ; magnified 150 diameters. 1, 

 from the regio olfactoria, transverse section of the mucous membrane : a, epitheUum without 

 cilia ; b, olfactory nerves, with a dividing, pale, nucleated fasciculus; c, one of "Bowman's 

 glands;" rf, its orifice. 2, ciliated epithelium of the Schneiderian membrane. 



