=The Pharynx= (Fig. 27). _Location._—The anterior part of the pharynx joins with the mouth and the posterior part with the upper portion of the esophagus and the superior larynx. The pharynx is bounded anteriorly by the base of the tongue and by the posterior edge of the hard palate. Posteriorly, it is marked by the entrance of the esophagus and by a ridge of filiform papillæ located on the supero-posterior part of the larynx, called the palatal papillaries. A few filiform papillæ stud the roof. The pharynx communicates anteriorly with the posterior nares and the mouth, and, posteriorly, with the esophagus and the larynx. _Shape._—The pharynx is a musculo-membranous sac. _Structure._—The pharynx is lined with a mucous membrane covered by squamous epithelium. The mucous membrane is thrown into irregular folds. The bird has two Eustachian tubes. Pneumatic apertures conduct the air from the Eustachian tubes to the pericranial diploë. In the posterior pharyngeal roof is situated the infundibular crevice. _Function._—The function of the pharynx is to give passage for the air from the posterior nares to the larynx, and to give passage for the food from the _mouth_ to the esophagus. =Glands Adjacent to the Mouth and to the Pharynx.=—The mucous membrane adjacent to the glottis and in the roof of the mouth contains alveolar glands. The _angular gland_ of the mouth, located beneath the zygomatic arch, by some anatomists is considered the rudimentary parotid gland. The _sublingual glands_, or glandulæ sublinguales, are well developed (Fig. 17, No. _B_, 4). They form conical masses, with the apex directed anteriorly, and occupy a portion of the intermaxillary space. Several ducts from these glands open into the mouth cavity. In the palatine region there are also located glands called the _palatine glands_, which open by many stomata upon the surface. =The Esophagus= (Fig. 18, No. 6). _Location and Shape._—The esophagus is a musculo-membranous tube, capable of great distension, which extends from the pharynx to the proventriculus (Fig. 35, No. 1, and 3). The esophagus communicates anteriorly with the pharynx. It extends down the neck, lying supero-laterally with regard to the trachea and toward the right side. It enters the thorax above the trachea, and, passing through between the bronchi, terminates into the proventriculus. At the entrance of the thorax and just to the right of the median line, it expands into the crop which divides it into two portions, designated as the first and the second. The first portion of the esophagus is the longer, the length depending upon the size and kind of fowl. _Structure._—The wall is composed of four coats, the mucous membrane, the submucosa, the muscular coats, and the fibrous sheath or tunic. The mucous membrane is pale and is covered with stratified squamous epithelium.