THE SINUS MAXILLARIS 



97 



Ost.f rotvt. 

 O st.-tr o n.t 



S.sp 



O st.tu b. a.ud. 



FIG. 36. SPECIMEN FROM A CHILD NINE YEARS, ONE MONTH, AND NINE 



DAYS OLD. (Series D, No. 64.) 



Incision through maxilla is ^ mm. to the right of median line; in the frontal 

 region 1 mm. to the left, and through the body of the sphenoid is 5 mm. to 

 the left of median line. The anterior portion of the concha media and a small 

 portion of the frontal bone have been removed to show the structures entering 

 into the formation of the lateral nasal wall, and also the location of the ostia 

 frontalia. In this case there are three sinus frontales one in the right side 

 and the two in the left side here illustrated. Of the more lateral sinus frontalis, 

 only the ostium is shown (Ost. front, (b) ); the sinus, however, extends to the 

 same height as the medial one shown in the illustration. Note that neither 

 ostium comes into direct relation to the infundibulum ethmoidale. In the 

 suprabullar furrow ostia of bullar cells are shown. S. front., Sinus frontalis; 

 C.front., conchse frontales; Ost.tub.aud., ostium pharyngeum tuba3 auditivse; 

 S.sph., sinus sphenoidalis; B.eth., bulla ethmoidalis; Proc.unc., processus 

 uncinatus; Ost.front.(b}, ostium of the lateral sinus frontalis; Ost. front. (a), 

 ostium of the medial sinus frontalis. 



