AUTHOR’S ABSTRACT OF THIS PAPER ISSUED 
BY THE BIBLIOGRAPHIC SERVICE, MAY 23 
EFFECTS OF CUTTING THE LINGUAL NERVE OF THE 
DOG 
J. M. D. OLMSTED 
Department of Physiology, University of Toronto 
SIX FIGURES 
It has been found that cutting the glossopharyngeal nerve of 
the dog results in the disappearance of the taste buds in the cir- 
-cumvallate papillae on the side of the tongue innervated by the 
severed nerve (Vintschgau und Héningschmied, ’76; Vintschgau, 
80; Drasch, ’87; Sandmeyer, 795; Semi Meyer, 796). Those 
investigators who studied the manner of disappearance of the _ 
taste buds, Vintschgau and Meyer, were convinced that degenera- 
tion did not take place, but rather a process of dedifferentiation 
or metamorphosis transposed the sense cells into indifferent 
epithelial cells. Ranvier (’88) performed this sane operation 
on the rabbit and claimed that the sense cells did undergo degen- 
eration and were completely destroyed on the spot. In another 
paper (Olmsted, ’20) I have described the changes occurring in 
the taste buds situated on the barbels of the fish, Amiurus nebu- 
losus, after cutting the appropriate branches of the facial nerve. 
With the fish, as with the rabbit, there were distinct degenera- 
tive processes observable at a certain time after the operation, 
accompanied by phagocytic action of leucocytes. I suggested 
that similar degenerative changes would probably be observable 
in the dog if one could happen upon a preparation taken at 
just the correct interval after severing the nerve. 
The mammalian tongue is innervated by two nerves, the 
glossopharyngeal, supplying the posterior third (including the 
circumvallate papillae), and the lingual, supplying the anterior 
two-thirds. All the operations on mammals to which reference 
has been made were on the glossopharyngeal nerve. This paper 
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