124 ^ MANUAL OF ANATOMY 



posterior borders of the two parietal bones. The two limbs of the 

 suture, right and left, become continuous with each other at the 

 superior angle of the tabular part of the occipital bone, from which 

 point each Hmb passes outwards and downwards. The margins of 

 the bones are strongly serrated, and along the course of the suture 

 supernumerary ossicles, called Wormian bones, are frequently present. 



The occipito-mastoid suture, on either side, connects the inferior 

 lateral border of the tabular part of the occipital bone with the 

 posterior border of the mastoid part of the temporal bone. It is 

 one of the bifurcations of the lower end of the corresponding limb 

 of the occipito-parietal suture, the other bifurcation being the 

 parieto-mastoid suture. Its direction is downwards and forwards. 



The interparietal or sagittal suture connects the superior borders 

 of the two parietal bones. It is serrated, and occupies the median 



Coronal Suture " 



Bregma 

 (Anterior Fontanelle) J 



■ Sagittal Suture 



, , , \ SeSK/^r' /Parietal Foramen 



Lambda \ i / 



(Posterior Fontanelle) -V- 7i''*ife'Vj_ / 



\ _j5^ — ^ '^i ■ X^-^mbdoid Suture 



Fig. 78. — Sutures of Superior Surface of Skull. 



line, its direction being from behind forwards. Posteriorly it meets 

 the lambdoid suture, the place of meeting constituting the lambda, 

 which indicates the situation of the posterior fontanelle of early life. 

 From the lambda three sutures radiate — namely, the interparietal 

 suture and the two limbs of the occipito-parietal suture. Anteriorly 

 the interparietal suture meets the coronal- suture, the place of 

 meeting constituting the bregma, which indicates the situation of 

 the anterior fontanelle of early life. The part of the sagittal suture 

 in the region of the two parietal foramina is usually less serrated 

 than elsewhere, and is the first part to show signs of obliteration. 

 It constitutes the obelion, which indicates the situation of the 

 sagittal fontanelle of early intra-uterine life. 



The fronto-parietal or coronal suture connects the supero-lateral 

 or parietal border of the frontal portion of the frontal bone with 

 the anterior borders of the two parietal bones. It crosses the 



