Mil I 



the external plate i der and d 



pterygoid fossa, \vlu\h is narrow al •< 



inferior boundary is formed by the tub ramidal j i 



i loses tin- spa< e, the pterygoid noU //, 



At the base of the internal plate then ill elliptical f 



, to the outer sidi rd the there j 



the cartilaginous portion of the Eustachian tube whi the middlt 



pharynx. At its lower end the internal plate terminates in the slcn 

 itnulus pterygoideu I at the 1 



.md forming a pulley for the tendon of the I 

 Beside the scaphoid fos ituated a small, flat, rather triangulai 



prut < Fig. 54), which is directed toward the sphenoidal rostrum; 

 process of the palate bones it aids in the- formation of the ph 



Upon the anterior surface of the pterygoid ; . runn: 



extremity oi the pterygoid canal, thru- is a shallow 



, which, with similarly named gi date and maxillar 



palatine canal, whose external orifices arc the palatine foramina of the ha: 

 40 and 78). 



Since the sphenoid bone is almo 1 tly in the center of the skull and h 



both the cranial and the facial bones, it articulates with a large numUr of th r.ull 



seepage 37 etseq.). These are the occipitals, the temporal, the parietal, the 1 

 the maxilla, the zygomatic, the palate, and the vomer. It also form- 

 middle, and posterior cranial fossae, of the orbit, of the nas 

 'he infratemporal fossae, ami of the sphenomaxillary fos 



A- regards the development of the sphenoid, it may 

 prion of the internal plates of the pterygoid pro 

 in membrani I 1 sification begins toward the- end of tin 

 and posterior portions of the body of the bone, so that for .1 lim< th i 

 U-hind the other. The lesser wings arise from spei ial cenl 



forming the outer plates of the pterygoid pi 

 of the sphenoid between the sixth and seventh fetal month-; the 

 until after birth; and the two halve- of the body of the sph( 

 that an inters phenoidai sync>; • exists for a e. 



The internal plate of the pterygoid process is foi 

 with the external plate. The sphenoidal turbinated Don 

 sphenoid until the age of puberty, and at th< 

 The sphenoidal sinus arises during i hildhood, hut in< n 

 fc * Variations are frequent in the sphenoid bone, 

 and their fusion with the anterior or posterior clinoid pr 

 page 119) there is not infrequently formed 



THE TEMPORAL BONE. 



The temporal bone Figs. 55 to 63 is situated in the lateral all, 



and forms portions of the middle and posterior cranial foss f the tem- 



poral bones fills in the large gap in the os be . ;■ . 



