306 SOFT PALATE. 



pass forward to the tip of the tongue ; others backward, 

 while another set are in the middle. 



Function. The anterior fibres can depress the tip of the 

 tongue, the posterior bring forward the os-hyoides and 

 protrude the tongue, while the middle set can make it con- 

 cave from side to side. 



Hyo-glossus (Fig. 87) is a quadrilateral muscle, arising 

 from the body and whole of the cornu of the os-hyoides, and 

 inserted into the side of the tongue between the stylo- 

 glossus and the lingualis. Function. To depress the sides 

 of the tongue, and thus render its dorsum convex. 



Stylo-glossus (Fig. 87,) arises tendinous and slender from 

 the styloid process near its apex or free extremity, and from 

 the stylo-maxillary ligament, and is inserted in two por- 

 tions, into the side of the tongue one portion blending 

 with the hyo-glossus, and the other being continued for- 

 ward to the tip of the tongue. 



Function. To raise the tip of the tongue against the 

 incisor teeth, and draw it backward, and to one side. 



Stylo-Jiyoideus (Fig. 86) is a small, delicate muscle, arising 

 near the base of the styloid process, on its outer side, pass- 

 ing obliquely forwards and inwards, parallel to the poste- 

 rior belly of the digastric, whose tendon perforates it. It 

 is inserted into the body of the os-hyoides. Function. To 

 draw back the os-hyoides and tongue, and thus assist the 

 posterior belly of the digastric. A ligament, called stylo- 

 hyoid, often accompanies this muscle, and is sometimes 

 found ossified. 



SOFT PALATE. 



The palate has been divided into hard and soft. The 

 hard is composed of the palatine plate of the palate 

 bones. The soft palate is attached to the posterior mar- 

 gin of the hard, and consists of a dense aponeurosis, 

 muscles and glands, enclosed in mucous membrane. The 

 soft palate, (velum pendulum palati,*) on depressing the 

 lower jaw, is seen at the posterior part of the mouth, sus- 

 pended transversely in the form of a membranous curtain. 



