THE SINUS FRONTALIS 



149 



S. f rorxt. 



Ce.l-i.n.f urtd- 



v Cel.eth..<xn.t. 



Cel.etH.post. 



S.spK. 



Infuad.eth. 

 Duct. aa. .ls.c r 



O st. max. 

 C st. max. Chi 



S. ma. x 



For rotuactum. 



FIG. 54. SPECIMEN TWENTY-TWO YEARS, Six MONTHS, AND ELEVEN DAYS 



OLD. (Series D, No. 93.) 



Lateral portions of the frontal, ethmoidal, maxillary, and sphenoidal areas 

 have been removed to show the extent and relations of the sinuses. Note 

 that two ostia maxillaria are present, both communicating with theinfundib- 

 ulum ethmoidale. (This is the only instance of this kind found in the entire 

 series.) Cel.eth.ant., Cellulse ethmoidales anterior; Cel.eth.post., cellulse eth- 

 moidales posterior; S.sph., sinus sphenoidalis; For.rotundum, medial wall of 

 foramen rotundum; S.max., sinus maxillaris; Ost.max.(b), ostium maxillare; 

 Ost.max. (a), duplication of ostium maxillare; Duct.na.lacr., ductus naso- 

 lacrimalis; Infund.eth., infundibulum ethmoidale; Cel.infund., cellulse in- 

 fundibulares; S. front., sinus frontalis. 



