OCCIPITAL BONE. 

 Fig. 12.* 



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the lambdoidal suture ; the inferior are rough, but not serrated, and 

 articulate with the mastoid portion of the temporal bone by means of 

 the additamentum suturae lambdoidalis. The jugular eminence and 

 the side of the basilar process articulate with the petrous portion of 

 the temporal bone, and the intermediate space, which is irregularly 

 notched, forms the posterior boundary of the jugular foramen, or fora- 

 men lacerum posterius. 



The angles of the occipital bone are the superior, inferior, and two 

 lateral. The superior angle is received into the interval formed by 

 the union of the posterior and superior angles of the parietal bones, 

 and corresponds with that portion of the foetal head which is called 

 the posterior fontanelle. The inferior angle is the articular extremity 

 of the basilar process. The lateral angles at each side project into that 



* The internal surface of the occipital bone. l. The left cerebral fossa. 

 2. The left cerebellar fossa. 3. The groove for the posterior part of the 

 superior longitudinal sinus. 4. The spine for the falx cerebelli, and groove for 

 the occipital sinuses. 5. The groove for the left lateral sinus. 6. The internal 

 occipital protuberance, the groove on which lodges the torcular Herophili. /. 

 The foramen magnum. 8. The basilar process, grooved for the medulla ob- 

 longata. 9. The termination of the groove for the lateral sinus, bounded ex- 

 ternally by the jugular eminence. 10. The jugular fossa; this fossa is com- 

 pleted by "the petrous portion of the temporal bone. 11. The superior border. 

 12. The inferior border. 13. The border which articulates with the petrous 

 portion of the temporal bone, and which is grooved by the inferior petrosal 

 sinus. 14. The anterior condyloid foramen. 



