The pharynx is short and wide. The vault (Fornix pharyngis) is divided
into two cul-de-sacs by a median fold of mucous membrane (Septum nasi
membranaceum), which is a continuation of that of the septum nasi; on
the outer wall of each is the relatively small opening of the Eustachian
tube, which is covered by a simple fold of mucous membrane. The
posterior nares are small. The entrance to the œsophagus is large.
[Illustration: