GENERAL REMARKS ON THE CRANIUM. 195 



to consist of three pieces,, viz : 1 and 2, the greater wings 

 and pterygoid processes of either side, and 3, the lesser wings 

 and body in a single piece. The sphenoidal spongy bones, 

 or pyramids of Wistar, belong also to the latter piece. Ossi- 

 fication is noticed in the various parts in the following 

 order, viz: 1. In the greater wing and external pterygoid 

 process, about the seventh or eighth week. 2. Lesser wings 

 and posterior body, at the close of the second month. 3. 

 Anterior body, at the end of the third month. 4. The in- 

 ternal pterygoid plate has a separate ossific point, which is 

 stated to unite with the external pterygoid about the middle 

 of the fourth month. The centres for the posterior portion 

 of the body, and those for the anterior and lesser wings, are 

 seen to unite first; then the greater wings and pterygoid 

 processes. The latter unite with the body during the first 

 year; the pyramids of Wistar join it about puberty, at which 

 time this bone becomes connected with the ethmoid ; while 

 the body of the sphenoid joins the occipital bone between 

 the eighteenth and twenty-fifth years. 



The sphenoid is articulated with all the bones of the cra- 

 nium and five of the face, viz: the two malar, two palati, 

 and the vomer. 



GENERAL REMARKS ON THE CRANIUM. 



Under the head of the osseous tissue the different articu- 

 lations were described. Synarthrosis was stated to denote 

 the articulation of bones that have no motion, and suture 

 the mode of union between the different bones of the cra- 

 nium. 



The c&ronal, the sagittal, the lambdoid, the squamous, the 

 sphenoid, and ethmoid, constitute the principal sutures. 

 (See Fig. 53.) 



The coronal suture connects the anterior edges of the pa- 

 rietal bones with the superior margin of the frontal, and 

 extends from side to side over the superior and anterior 

 surface of the cranium. 



The sagittal unites the parietal bones along the median 

 line, and extends, from the superior angle of the occipital 



