246 
ANATOMY OF THE RABBIT. 
In the oral cavity: 
(a) 
(b) 
(c) 
(d) 
The hard palate (palatum durum) forms the anterior 
portion of the roof; its mucous membrane is thrown into a 
series of transverse ridges. 
The soft palate (palatum molle) is the thin, narrow, 
posterior, membranous portion of the roof. It is very long 
in the rabbit, extending from the bony palatine bridge 
backward to a point above the laryngeal aperture, where it 
ends with a concave free margin. 
The nasopalatine or incisive ducts (dd. nasopalatini) 
open by minute apertures immediately behind the small 
incisors. They connect the anterior portion of the nasal 
cavity with the mouth. 
The tongue (lingua) projects upward and forward from its 
basal attachments on the hyoid into the floor of the mouth. 
Its connection with the latter is extended forward in the 
middle line by a vertical membranous fold, the frenulum 
linguae. Its dorsal surface is divided into a posterior 
smooth and hard portion, and an anterior softer and rougher 
portion, occupied by fine low elevations, the fungiform 
papillae (papillae fungiformes). At the posterior end of the 
smooth portion there is on either side a miaute spherical 
elevation, set low into the mucous membrane, the vallate 
papilla (papilla vallata), and in a more lateral and anterior 
position an oval area, the papilla foliata, the surface of 
which is marked by fine parallel ridges. Both vallate 
and foliate papillae are occupied by microscopic taste-buds. 
In the pharynx: 
(a) 
(b) 
The tonsil (tonsilla) appears as a rounded mass of lymph 
follicles lying on the anterior wall of a deep lateral depres- 
sion, the tonsillar sinus (sinus tonsillaris). The vertical 
slit-like aperture of the sinus is bounded by low anterior 
and posterior folds. 
The epiglottis, a valve-like fold guarding the entrance 
to the larynx, projects upward from the floor into the 
pharyngeal cavity. 
By removing the posterior portion of the soft palate, the 
connection of the nasopharynx with the nasal fossae will be 
