The roof of the mouth is thus exposed. Dissect next—
14. The pterygoid muscles ([Fig. 66]). Remove the mucosa of the roof of the mouth, especially at the sides of the soft palate, and the two pterygoid muscles ([p. 111]) are exposed. The lower jaw may be removed on one side to get at their origin.
(The muscles of the soft palate ([p. 230], and [Fig. 66], d and e), and the superior constrictor of the pharynx ([p. 233], and [Fig. 66], f) may be observed at this point, if desired.)
V. Muscles of the Wall of the Thorax and of the Abdomen.
1. The scalenus ([p. 141], and [Fig. 73], f-f‴). To trace its cervical portion, cut the trachea and œsophagus just craniad of the first rib, cut the pharynx and hyoid free from the ventral side of the head and neck, and remove the pharynx, larynx, œsophagus, and trachea (these should be preserved for future study of the larynx).
2. The transversus costarum ([p. 150], and [Fig. 73], j).
3. The serratus posterior superior ([p. 148], and [Fig. 73], l). Transect this at about the middle of the muscle-bundles, and reflect it in both directions.
4. The serratus posterior inferior ([p. 148], and [Fig. 73], n). Transect and reflect as in the last.
5. The external oblique ([p. 153], and [Fig. 68], p). Transect it by an incision parallel to its tendon of origin and about an inch from it, and reflect in both directions.
6. The internal oblique ([p. 154], and [Fig. 73], o). Transect and reflect as above.