376 



MAMMALIAN ANATOMY 



the orbital surface from the superior surface of the palatine plate. Just 

 behind and parallel to the anterior border is a deep and wide vertical 

 groove, the lachrymal groove, which lodges the lachrymal duct and is 



FIG. 294. 



Posterior part of Frontal Sinus. Sagittal Suture. 



Orbital Ridge. 



Opening into Anterior part of Frontal 

 Khnts, with Posterior end of Lat- 

 eral Ethmoid. 



Foramina for Olfactory Filaments. 





Median Plate of Frontal.- y ^-V^ 

 Orbital Plate of Frontal. 



'II ' I 1 



Cut Edge of Cribriform Plate. 



Cribriform Plate of 

 Ethmoid. 



Mesethmoid. 

 Sinus. 



Vertical Plate of Pala- 

 tine. 



Vomer. 

 Lachrymal. 



Zygoma. 



Malar. 



Maxillary. 



Tuberosity. Infraorbital ' 1 ^ 

 Foramen, hs ~ t 



Alveolar Border. 



s. 

 ?? 







i3 



2 ' 



TRANSVERSE VERTICAL SECTION OF SKULL THROUGH ORBITS, SEEN FROM BEHIND. 



the beginning of the lachrymal canal. Several foramina are to be 

 seen in the upper part of the groove. The groove is separated from 

 the rest of the orbital surface by the lachrymal crest, the lower end 



FIG. 295. 



Lachrymal Groove and Notch. 

 With Maxillary 



With Malar 



With Frontal and Os Planum of 

 Ethmoid when present. 



With Palatine. 



With Maxillary. 

 LEFT LACHRYMAL BONE, OUTER SURFACE. 



of which curves upward to form the upper root of the hamulus, or 

 hook, a small blunt process arising from the orbital surface just behind 

 and above the anterior-inferior angle and articulating with the lach- 



