TASTE FIBERS IN CHORDA TYMPANI 339 
tongue immediately after the animal’s death. These were fixed 
at once, and sectioned and stained in the usual manner (Olmsted, 
21). At the same time the head was dissected. It was found 
that in both dogs the left chorda tympani had been severed, 
while the lingual remained unharmed. ‘The results given in table 
1 show that all papillae which were examined from the operated 
side—twelve in one, fourteen in the other—were lacking in taste 
buds, or the taste buds were in a late stage of degeneration. 
Papillae from corresponding regions on the unoperated side were 
normal in every respect. 
TABLE 1 
RNQRINELE Nan er es NUMBER PAPILLAE 
WITH NORMAL 
TASTE BUDS 
NUMBER PAPILLAE 
WITHOUT 
TASTE BUDS 
poa | NUMBER PAPILLAE 
| EXAMINED DEGENERATING 
TASTE BUDS 
Left chorda tympani cut 
No. 12 174 11 i 0 
No. 13 14 12 2 0 
Right side uninjured 
No. 12 6 0 0 6 
No. 13 9 0 0 9 
Left mandibular nerve cut 
No.4 | 14 | 0 | 0 | 14 
Operation as extensive as in cutting chorda, but chorda left intact 
No.6 | Teton! | oy, 1 0 | 7 
Further proof that the injury of operation was not the cause of 
the disappearance of the taste buds is afforded by the results 
of operations on three dogs in which the attempt to cut the chorda 
tympani was unsuccessful. The incision in all these operations 
is made just anterior and mediad to the angle of the jaw (following 
the directions given in figures 238, 239, 240 of Jackson’s Experi- 
mental Pharmacology). After the lingual nerve is disclosed it 
can be easily traced to the point where it passes between the 
pterygoid muscles. The tendinous attachments of these muscles 
must be cut and the tissues separated clear to the tympanic 
bulla of the temporal bone in order to lay bare the chorda tym- 
