Kinesspury, Columella Auris and N. Factalts. Br7 
processus basilaris quadrati, "passes forward and outward under 
the quadratum to the outer surface of the squamosum, passing 
in front of (ventrad and cephalad to) the ligament. 
The ramus palatinus which passes forward through a fora- 
men distinct from that for the rest of the facial nerve, and the 
ramus mandibularis internus which passes immediately ventrad 
from the cephalic edge of the accessory lateral line ganglion, 
do not come into close relation to the columella, but are, of 
course, morphologically below and in front of it. 
In an older Necturus, 9.4 c.m. long, the relations are as in 
the specimen just described, save that the processus ‘‘staped- 
ialis’”’ of the squamosum has attained an appreciable length, and 
the operculum possesses a short ossified stalk to which the liga- 
Fig. 2a. Section of the Necturus embryo 19 mm. in length. c.—anlage of the 
squamoso-columellar ligament; 4.—hyoid: v. 7.—vena jugularis ; 2. 7.— 
nervus jugularis ; @. #.—M. depressor mandibuli; s.—squamosum. 
Fig. 26. Same, three sections farther forward. 
ment attaches. Neither ossification appears to be an ossifica- 
tion of the ligament, but ossifications of the squamosum and 
operculum at each end of the ligament, acomplishing in that 
way the increase in length due to growth. In the adult, the 
operculum possesses an ossified process of some length joined 
