168 MUSCLES OF THE SOFT PALATE. 



Sixth Group. Muscles of the soft Palate. 



Levator palati, 

 Tensor palati, 

 Azygos uvulae, 

 Palato-glossus, 

 Palato-pharyngeus. 



Dissection. To examine these muscles, the pharnyx must be 

 opened from behind, and the mucous membrane carefully removed 

 from off the posterior surface of the soft palate. 



The levator palati, a moderately thick muscle, arises from the 

 extremity of the petrous bone and from the posterior and inferior 

 aspect of the Eustachian tube, and passing down by the side of the 

 posterior nares spreads out in the structure of the soft palate as far 

 as the middle line. 



Relations. Externally with the tensor palati and superior con- 

 strictor muscle ; internally and posteriorly with the mucous mem- 

 brane of the pharynx and soft palate ; and by its lower border with 

 the palato-pharyngeus. 



This muscle must be turned down from its origin on one side, 



and removed, and the superior con- 

 Fig. 74 * strictor dissected away from its 

 pterygoid origin, to bring the next 

 muscle into view. 



The tensor palati (circumflexus) is 

 a slender and flattened muscle ; it 

 arises from the scaphoid fossa at the 

 base of the internal pterygoid plate 

 and from the anterior aspect of the 

 Eustachian tube. It descends to the 

 hamular process around which it 

 turns, and expands into a tendinous 

 aponeurosis, which is inserted into 

 the transverse ridge on the horizontal 

 portion of the palate bone, and into the raphe. 



Relations. By its external surface with the internal pterygoid 



*The muscles of the soft palate. 1. A transverse section through the middle of the 

 base of the skull, dividing the basilar process of the occipital bone in the middle line, 

 and the petrous portion of the temporal bone at each side. 2. The vomer covered by 

 mucous membrane and separating the two posterior nares. 3, 3. Eustachian tubes. 4. 

 The levator palati muscle of the left side ; the right has been removed. 5. The ha- 

 mular process of the internal pterygoid plate of the left side, around which the apo- 

 neuorosis of the tensor palati is seen turning. 6. The pterygo-m axillary ligament. 7. 

 The superior constrictor muscle of the left side, turned aside. 8. The azygos uvuke 

 muscle. 9. The internal pterygoid plate. 10. The external pterygoid plate. 11. The 

 tensor palati muscle. 12. Its aponeurosis expanding in the structure of the soft palate. 

 13. The external pterygoid muscle. 14. The attachments of two pairs of muscles cut 

 short ; the superior pair belong to the genio-hyo-glossi muscles ; the inferior pair, to 

 the genio-hyoidei. 15. The attachment of the mylo-hyoideus of one side and part of 

 the opposite. 16. The anterior attachments of the digastric muscles. 17. The de- 

 pression on the lower jaw corresponding with the submaxillary gland. The depression 

 above the mylo-hyoideus, on which the number 15 rests, corresponds with the sub- 

 lingual gland. 



