M. hyoglossus (h).—From the body of the hyoid bone to the tongue.
Origin.—(1) From the ventral surface of the body of the hyoid laterad of the geniohyoid (g), and (2) by a second head from the ceratohyal.
Insertion.—Both heads penetrate into the tongue between the styloglossus (e) and the genioglossus (f). The fibres intermingle with those of the styloglossus (e) and thus help to form the lateral parts of the tongue. They finally end in the integument on the dorsum of the tongue at the sides.
Action.—Retracts the tongue and depresses it.
M. styloglossus (e).—From the stylohyal bone to the tongue.
Origin from the mastoid process of the temporal bone, from the stylomandibular ligament (2) (which connects the border of the external auditory meatus with the angular process of the mandible) and from the proximal cartilaginous portion of the cranial cornu of the hyoid bone. The fibres pass mediad, diverging between those of the digastric and hyoglossus (h) into the lateral part of the tongue.
Insertion.—The fibres pass toward the tip of the tongue, where the mass finally ends in a point, the superficial ones gaining insertion into the integument at the sides of the tongue.
Relations.—Outer surface with the digastric ([Fig. 65], b) and mylohyoid ([Fig. 65], c). Inner surface with the pterygoideus internus ([Fig. 96], d), the cranial cornu of the hyoid, and the tympanic bulla.
Action.—Retracts the tongue and raises it.
