Monro, Alexander: Observations on the structure and functions of the nervous system: illustrated with tables (Edinburgh [u.a.], 1783)

is-8 EXPLANATION OF THE TABLES.


T A B L E XXX.
Epresents the os petrosum diiTe&ed, after being sof-
tened, so as to ssiew the distribution of the portio dura
and portio mollis of the seventh pair, but chiessy of the latter.
Fig. I. Represents the back view, and Fig. II. the fore view of the os
petrosum, and parts of the left side.
Fig. I.
A The inner end of the os petrosum.
B The outer end of the os petrosum.
C The back of the external ear. ,
D The posterior end of the superior semicircular canal.
E The superior end of the posterior semicircular canal joining with D.
F The inferior end of the posterior semicircular canal.
G The portio dura in the meatus auditorius internus, situated in a half
ssieath, formed by the portio mollis.
H The continuation of the portio dura.
IK The two principal parts of the portio mollis. I Ends in the cochlea,
and K in the vestible and semicircular canals.
Fig. II.
A The upper and fore part of the cartilage of the external ear.
B The meatus auditorius cut open its whole length.
C The membrane of the drum.
D The malleus.
E The incus.
F The head of the stapes.
G The