Olfactory Apparatus in Dog, Cat and Man 37 



the appearance of these' nerve fibers within tlie nasal epithelium, but 

 does not wish to give his verdict as to their origin, he adds that it is 

 plausible that these are of a sensory nature. In his work on Fishes he 

 does not find any structures comparable with the "Geruchsknospen" of 

 Blaue. Eetzius considers as false the theory of Blaue that there are 

 such structures which have sense cells in direct connection with the 

 olfactory nerve. 



Cajal, 189Jf, in his Systeme Nerveux denies having committed him- 

 self upon the character of these nerves, but ascribes their discovery to 

 von Brunn. According to his work, the endings of the 5th nerve are 

 found only in the submucosa and do not extend into the epithelium. 

 He finds in man fibers which end free at the surface of the epithelium, 

 but these are nearly vertical and end in a conical projection at the top, 

 as is shown by von Lenhossek. He withholds his verdict as to the 

 origin of the fibers thus ending until work then in progress was com- 

 plete. He has seen them only in the embryo, but never in new-born 

 animals or those several days old. 



Disse, 1896, found in the nasal mucosa of some mammals "Epithel- 

 knospen" which resemble the taste buds in appearance. These buds 

 are of two kinds, the large buds in the olfactory epithelium and the 

 small buds in the respiratory epithelium. These consist of supporting 

 cells and sense cells^ (the sense cells are not ganglion cells). By the 

 Golgi method he traced nerve fibers into the large buds. He considers 

 these fibers as belonging to the 5th nerve. Disse does not credit Blaue's 

 theory that these buds are in connection with the olfactory nerves, but 

 thinks that they have to do especially with the sweet and sour sense of 

 taste in the nose. 



Kallius, 1905, has seen the free endings of the 5th nerve in the 

 respiratory and olfactory epithelium of calf. He finds nothing in his 

 preparations, except possibly nests of mucous cells, which in any way 

 resemble the "Epithelknospen" of Disse, nor have any such structures 

 been found in the nasal epithelium of man. 



Personal Observations. 



I have seen in the nasal epithelium of the kitten a few days old, 

 both in the respiratory and olfactory regions, many much-branched 

 nerve fibers. These were varicose and often ended with a varicosity 

 (Figs. 44, 45). From the gross dissection, fibers from the 5th nerve 



