28 



Bones of the Skull. 

 Processus front alls 



Union with the os nasale 



Union with the pars 

 nasalis ossis frontalis 



Margo lacrimalis 

 / Sulcus lacrimalis 



/ / Union with the 

 / lamina papyracea 

 oss. ethmoidalis -^ 



Crista ethmoidalis 



Crista conchalis 



Facies nasalis 

 Incisura nasalis 



Spina nasalis anterior 



Surface for apposition with the 

 proc. orbitalis ossis palatini 



. Hiatus maxillaris 



Surface for apposition with 



the pars perpendicularis 



ossis palatini 



Corpus maxillae 



- Crista nasalis 



- Groove for the completion of 

 the canalis pterygopalatinus 



- Processns alveolar!* 



Canalis incisivus 



35. Right upper jaw bone, maxilla, from within. 



The fades nasalis of the corpus maxillae (see also Figs. 7374) is placed sagittully 

 and helps to form the lateral wall of the nasal cavity. A large opening in it, the hiatus 

 maxillaris, leads into the sinus maxillaris (0. T. antrum of Highmore). The slightly rough 

 field behind the hiatus has attached to it the facies maxillaris of the pars perpendicularis oss. 

 palatini and presents usually a smooth perpendicular groove for the completion of the canalis 

 pterygopalatinus; the area behind this groove serves for apposition with the proc. pyramidalis 

 oss. palatini. In front of the hiatus in the upper part passing downward from the posterior 

 margin of the proc. frontalis is the sulcus lacrimalis which is closed to form the canalis 

 nasolacrimalis (0. T. lachrymal groove) by the attachment to it medianward of the os lacrimale 

 above and the proc. lacrimalis conchae nasalis inferioris below. In front of this the crista 

 conchalis (for union with the upper border of the concha nasalis inferior) runs approximately 

 horizontally forward. The anterior margin, incisura nasalis, helps to bound the apertura 

 piriformis. 



The processus frontalis (0. T. nasal process) (see also Figs. 34, 5558, 6770, 73 

 and 74) ascends in front from the upper margin of the facies nasalis and facies anterior. Its 

 upper, thick, serrated margin lies upon the pars nasalis oss. frontalis (sutura frontomaxillaris) ; 

 the anterior, sharp, slightly serrated margin unites with the os nasalis (sutura nasomaxillaris). 

 The posterior broad margin presents a groove, sulcus lacrimalis, which leads downward on 

 the facies nasalis of the body (vide supra) ; it is bounded medianward by the margo lacrimalis, 

 to which is attached the anterior margin of the lachrymal bone (sutura lacrimomaxill aris) , 

 lateralward by the slight crista lacrimalis anterior, which goes over into the margo infra- 

 orbitalis; behind this point of transition is situated the incisura lacrimalis, of variable depth, 

 in which is placed the hamulus lacrimalis oss. lacrimalis. The lateral surface is smooth; on 

 the medial, running from behind forward, is the crista ethmoidalis (for apposition with the 

 anterior extremity of the medial surface of the labyrinth). 



The short, broad processus zygomaticus (0. T. malar process) (see also Figs. 34, 

 57, 58 and 69 72) proceeds from the lateral upper angle of the body of the upper jaw and 

 is generally hollowed out inside for a bulging of the sinus maxillaris. Its surface is rough, 

 sometimes incomplete, and unites with the os zygomaticum to form the sutura zygomatico- 

 maxillaris. 



