. Transactions. lateralseparation of the facial canals above the oval windowsand comparing this with the distance between the stylo-mastoid foramina. One first point noted has been the almost unvarying sym-metry of finding on the two sides—the specimen presented(Fig. 4) being the sole notable exception. As the jugularbulb was often hugely larger on one side {vide these , and Trans. Pan-American Congress 189S), this 296 RANDALL. factor in the growth and ultimate configuration of the boneseems to be devoid of any influence upon the direction ofthe facial canal. In the sagital plane the
. Transactions. lateralseparation of the facial canals above the oval windowsand comparing this with the distance between the stylo-mastoid foramina. One first point noted has been the almost unvarying sym-metry of finding on the two sides—the specimen presented(Fig. 4) being the sole notable exception. As the jugularbulb was often hugely larger on one side {vide these , and Trans. Pan-American Congress 189S), this 296 RANDALL. factor in the growth and ultimate configuration of the boneseems to be devoid of any influence upon the direction ofthe facial canal. In the sagital plane there was an equalabsence of deviation from the perpendicular—a very fewspecimens showing forward inclination up to 5°, while anybackward course seemed due entirely to the large size ofthe exit and the deeper penetration of the probe into thecurve of the canal above. In this respect symmetry wasnot complete but the deviation was very rare and relation to skull-index the varying findings as to lateral. Fig. 4. Skull sectioned m Reids base line and through facial canals, which are curvedby reason of unequal encroaching para-mastoids. (Authors preparation.) divergence from the perpendicular seemed without mean-ing. The absolutely vertical position of the descendingportion of the facial canal was met in all types of skullfrom the extreme dolichocephalic to the extreme brachy-cephalic (.61 to .97.) The same must be said of theoutward and the inward deviation, with no preponderantoccurrence of either. Coming now to the exact point of Schwartzes contentionof oiitzvard inclination of the descending portion of thefacial canal in the transverse plane, we have to note a SURGICAL RELATIONS OF THE FACIAL CANAL. 297 considerable proportion of such deviations in an unimpor-tant degree. Sixty-five or some 13% showing a measurableoutward deviation, while in fifteen the possibility of suchdeviation was not absolutely excluded, the precise axis ofthe canal being slightly in doubt. Of
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