THE CELLULE ETHMOIDALES 



55 



FIG. 17. SPECIMEN FROM A CHILD EIGHT DAYS OLD. (Series D, No. 1.) 

 By sagittal sections removing the lateral portion of frontal bone, lamina 

 papyracea of ethmoid, and lateral portion of maxilla the sinus maxillaris, 

 cellulse ethmoidales, anterior and posterior, infundibulum ethmoidale, and the 

 primitive sinus frontalis are brought into view. S.front., Primitive sinus 

 frontalis; Duct.na.lacr., ductus nasolacrimalis; S.max., sinus maxillaris; 

 Cel.eth.post., cellulse ethmoidales posterior; Cel.eth.ant., cellulse ethmoidales 

 anterior; Infund.eth., infundibulum ethmoidale. 



S.spK. 



Hypoph, 



FIG. 18. SPECIMEN FROM A CHILD EIGHT DAYS OLD. (Series D, No. 1.) 

 Sagittal section in median line through frontal and maxillary bones and 3 

 mm. to left of median line through sphenoid bone. Shows the left lateral 

 nasal wall, the ascending and the descending rami of the meatuses, also the 

 extent of development of the sinus sphenoidalis. Note that the antero-inferior 

 wall of the sinus sphenoidalis (concha sphenoidalis or ossiculum Bertini) is 

 well ossified. Ag.na., Agger nasi; Ca.inc., canalis incisivus; Ramidesc., 

 rami descendens of ethmoidal meatuses; Ost.tub.aud., ostium tubse auditivse; 

 Hypoph., hypophysis; S.sph., sinus sphenoidalis; Rami asc., rami ascendens 

 of ethmoidal meatuses. 



