ANATOMY IN A NUTSHELL. 



369 



The orbit communicates with the cavity of the cranium by (1) the optic fora- 

 men and (2) the sphenoidal fissure. It communicates with four fossa?, (1) with 

 the nasal fossa by the nasal duct. (2) with the temporal fossa, (3) with the 

 zygomatic fossa. (4) and with the spheno-maxillary fossa. These last three by 

 the spheno-maxillary fissure. 



Each orbit has nine foramina. — (1) supraorbital, (2) infraorbital. (3) an- 

 terior ethmoidal, (4) posterior ethmoidal. (5) optic. (6) sphenoidal fissure, (7) 

 spheno-maxillary fissure. (8) nasal duct, (9) malar foramina. 



LESSON CV. 



The floor is formed by three bones, (1) the orbital surface of the superior 

 maxillary; (2) the orbital process of the malar; (3) the orbital process of the 



PLATE CLXXXIX. 



CPTIC TRACT 

 3RD CRANIAL N. 

 EXTERNAL GENICULATE BODY. . 

 MIDDLE PEDUNCLE 



-OPTIC TRACT. 

 4TH CRANIAL NERVE. 

 -EXTERNAL GENICULATE BODY. 



MOTOR RCOT OF bTH N. 

 SENSORY RCOT OF 5TH N. 



"GREAT HORIZONTAL FISSURE' 



The Inferioe View of the Cerebellum. 



palate. The floor is somewhat fiat and has (1) the infraorbital canal; (2) a 

 depression for the Inferior oblique muscle anteriorly; (•">) the infraorbital groove 

 posteriorly; (4) the palato-maxillary suture posteriorly. The root' is formed 

 by the two bones. (1) the orbital plate of the frontal bone anterior- 

 ly; (2) the lesser wing of the sphenoid posteriorly. The ROOF is dome-like. 

 At its outer angle is the lachrymal fossa for the lachyrmal gland. The depr< ssion 

 for theSuperior oblique muscle is at the inner angl< . Tin inner wall is formed 

 by four bom s, (1) the nasal proc< ss of the superior maxillary ; (2) the lachrymal 

 bone; (3) the os planum of the ethmoid; (4) body of the sphenoid. 



It has,(l) lachrymal crest;(2) groove for lachrymal sac; (3) ethmo-lachry- 

 mal suture; (4) ethmo-sphenoidal foramina. 



