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upwards and opens into the under surface of the broad flattened canal 
which forms the distal or vestibular portion of the vagina ( vg .). The 
two sections of the vagina overlap one another to a slight extent, the 
posterior end of the vestibular portion forming a very shallow blind 
pouch or cul-cle-sac into which a pair of accessory glands (gl. ac. gen.) 
opens. 
At the uterine extremity of the vagina, its epithelium is partially 
prolapsed into the cavity of the uterus in the form of a rosette with a 
depressed central portion, which marks the site of the opening of the 
narrow lumen of this portion of the vagina. The epithelium of the 
cervical portion is composed of columnar cells, the arrangement of which 
is complicated by the fact that the epithelium is thrown into a series 
of deep longitudinal folds, with the result that in longitudinal sections 
(see Plate XXVI, fig. 7), the nuclei of the cells appear to be scattered 
indiscriminately through the entire thickness of the epithelium. The 
thin chitinous intima everywhere maintains its connection with the free 
margins of the epithelial cells, dipping down in the deep narrow clefts 
which divide the longitudinal folds. The epithelial layer is surrounded 
by a thick sheath formed of several layers of circularly-disposed muscle 
fibres (m. vg.). This muscular sheath is continuous behind with the 
muscular layer of the wall of the uterus ( m.ut.), but at the anterior 
extremity of the cervical portion of the vagina, it comes to an abrupt 
termination. From the dorsal surface of the muscular sheath, several 
small bundles of muscle fibres arise, some of which pass, upwards and 
forwards, directly to their places of attachment to the proximal end of 
the vestibular portion of the vagina, while others, arising from the 
lateral portions of the dorsal surface of the muscular sheath, pass 
upwards and obliquely forwards, and crossing each other on the way 
are inserted into the opposite sides of the proximal end of the vestibular 
portion of the vagina. 
In addition to the above-mentioned muscles, a number of fibrils, 
which appear to be muscular in nature, are present in the epithelial 
layer. They arise from the inner surface of the circular muscular sheath 
and pass directly towards the lumen of the vagina, their extremities 
being lost among the epithelial cells, or in some cases they apparently 
reach, and become attached to, the inner surface of the chitinous iutima. 
The vestibular portion of the vagina (vg.) consists of a broad flattened 
tube which leads directly to the external genital opening. Its chitinous 
lining is considerably thicker than that of the preceding portion, and 
its exposed surface is completely covered with minute pointed scale-like 
