

OCCIPITO-FRONTALIS. 



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Fig. 68.* 



Dissection. The occipito-frontaKs is to be dissected by making a 

 longitudinal incision along the vertex of the head, from the tubercle 

 on the occipital bone to the root of the nose ; and a second incision 

 along the forehead and around the side of the head, to join the two 

 , extremities of the preceding. Dissect the integument and superficial 

 fascia carefully outwards, beginning at the anterior angle of the 

 flap, where the muscular fibres . are thickest, and remove it alto- 

 gether. This dissection requires care ; for the muscle is very thin, 

 and without attention would be raised with the integument. There 

 is no deep fascia on the face and head, nor is it required ; for here 

 the muscles are closely applied against the bones upon which they 

 depend for support, whilst in the extremities the support is derived 

 from the dense layer of fascia by which they are invested, and 

 which forms for each a distinct sheath. 



The occipito frontalis is a broad 

 musculo-tendinous layer, which 

 covers the whole of one side of 

 the vertex of the skull, from the 

 occiput to the eyebrow. It arises 

 by tendinous fibres from the 

 outer two-thirds of the superior 

 curved line of the occipital bone, 

 and from the mastoid portion of 

 the temporal; it is inserted into 

 the orbicularis palpebr arum muscle 

 and the internal angular process 

 of the frontal bone. The muscle 

 is fleshy in front over the frontal 

 bone and behind over the occipi- 

 tal, the portions being connected 

 by a broad aponeurosis. The two 

 muscles cover the whole of the 

 vertex of the skull, hence their 

 designation galea capitis ; they are 

 loosely adherent to the pericranium, but very closely to the in- 

 tegument, particularly over the forehead. 



* The muscles of the head and face. 1. The frontal portion of the occipito-frontalis. 

 2. Its occipital portion. 3. Its aponeurosis. 4. The orbicularis palpcbrarum, which 

 conceals the corrugator supercilii and tensor tarsi. 5. The pyramidalis nasi. 6. The 

 compressor nasi. 7. The orbicularis oris. 8. The levator labii supcrioris alsaque nasi. 

 The figure is placed on the nasal portion. 9. The levator labii superioris proprius ; 

 the lower part of the levator anguli oris is seen between the muscles 10 and 11. 10. 

 The zygomaticus minor. 11. The zygomaticus major. 12. The depressor labii infe- 

 rioris. 13. The depressor anguli oris. 14. The levator labii inferioris. 15. The su- 

 perficial portion of the masseter. 16. Its deep portion. 17. The attrahens aurem. 18. 

 The buccinator. 1 9. The attolcns aurem. 20. The temporal fascia which covers in 

 the temporal muscle. 21. The retrahcns aurem. 22. The anterior belly of the digas- 

 tricus muscle ; the tendon is seen passing through its aponeurotic pulley. 23. The 

 stylo-hyoid muscle pierced by the posterior belly of the digastricus. 24. The mylo- 

 hyoidcus muscle. 25. The upper part of the sterno-mastoid. 26. The upper part of the 

 trapezius. The muscle between 25 and 26 is the splenius. 



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