Insertion into the middle of the ventral surface of the body of the hyoid bone. Some of the fibres of the mylohyoid (c) are inserted into its tendon.
Relations.—Outer surface with the submaxillary gland (2) and the submentalis muscle. Inner surface with the digastric (b), the hyoglossus ([Fig. 67], h), and the geniohyoid ([Fig. 67], g).
Action.—Raises the hyoid.
M. geniohyoideus ([Fig. 67], g).—The geniohyoid is a long slender muscle which lies next to the median line between the symphysis menti and the hyoid bone, closely applied to its fellow of the opposite side and within (dorsad of) the mylohyoid ([Fig. 65], c).
Origin from the ventral half of the inner surface of the mandibula for about one millimeter from the symphysis.
Insertion by muscle-fibres into the lateral half of the ventral surface of the body of the hyoid bone.
Relations.—Outer (ventral) surface with the stylohyoid ([Fig. 65], d) and the mylohyoid ([Fig. 65], c); medial border with the muscle of the opposite side. Lateral border with the hyoglossus ([Fig. 67], h) and genioglossus ([Fig. 67], f). Inner (dorsal) surface with the genioglossus.
Action.—Draws the hyoid forward.
M. jugulohyoideus ([Fig. 67], b).—The jugulohyoid is a small flat quadrangular muscle covering the outer part of the ventral surface of the tympanic bulla.
Origin from the ventral border of the jugular process.