ANATOMY OF THE ELEPHANT'S EAR. 
13 
point about corresponding to that extremity of its lower 
bony wall from which the left hand or posterior extremity 
of the semi-detached fragment seen in the illustration has 
broken away. An elongated hiatus in the inner and lower 
wall of the canal (nearly 15 millimeters long and from 2 
to 4 millimeters wide) shows that the facial nerve in its 
passage above the roof of the upper tympanum is not 
entirely separated from the latter cavity by a bony partition. 
The elongated hiatus seems to be at its posterior extremity 
continued into a line of suture, which exists on the inner 
or mesial aspect of the canal, runs throughout the entire 
length of the canal, and appears to be a line of apposition 
or suture between the periotic and tympanic bones. 
Whether, however, this may not be a suture line between 
these two bones united together on the one hand and the 
squamosal on the other, I can not determine from the 
specimen before me, at least in its present condition and 
without further and very destructive, not to say violently 
disruptive, dissection, the lines of suture in the deeper 
parts of the specimen being very narrow, their course 
very tortuous and complicated, and the union between the 
component bones of the specimen being one of veritably 
rocky firmness. Neither can I discover an elucidation of 
this point in the few books on anatomy readily at my 
command. 
As shown in the illustration, the Fallopian canal near 
its external mouth at the stylo-mastoid foramen becomes 
greatly dilated. The diameter of this outer dilated portion 
— and consequently that of the aforesaid foramen — is 14 
millimeters ; its length, or depth, from the posterior surface 
of the skull is about two centimeters. At the inner (and 
forward) extremity of this dilated portion the facial canal 
is joined by another canal having a diameter of 3 or 4 
millimeters, which, running upwards, forwards, and 
inwards from this point of junction with the facial, 
