SKULL AND VISCERAL SKELETON OF THE GREENLAND SHARK. 305 



D. Cartilaginous partition (incomplete) between cranial cavity and pre-frontal fossa. 

 Ds. Dorsum sellae. 



E. Eye-stalk. 



El-5. Epi-branchial cartilages. 



e. Cut extremity of eye-stalk on skull. 

 em. Ethmoidal foramen (upper). 

 em'. Ethmoidal foramen (lower). 

 E/', Ew', Ew", Ew'". Extra-branchial cartilages. 



F. Prominence at hinder part of sclerotic for articulating with cup of eye stalk. 

 g, g'. Heads of hyo-mandibular cartilage. 



Op. Glosso-pharyngeal foramen (inner). 

 Op'. Glosso-pharyngeal foramen (outer). 

 Hl-4. Hypo-branchial cartilages. 

 He. Hypophysis canal. 

 H/i. Hypo-hyal cartilage. 

 Hm. Hyomandibular cartilage. 



lo. Inner opening of inter-orbital canal. 



Io'. Outer opening of inter-orbital canal. 



J. Point of articulation of upper and lower jaws. 

 j,f. Cranio-hyoid depression. 



K. Keel at lower part of internasal septum. 

 KA. Cerato-hyal cartilage. 

 Krl-5. Cerato-branehial cartilages. 

 L L' L". Labial cartilages. 



M. Anterior limit of pituitary fossa. 



to. Proximal (cut) extremity of eye-stalk. 



to'. Distal extremity of eye-stalk. 

 Mra. Lower jaw. 



N. Nasal capsule. 



n. Nodule of cartilage surmounting palato-basal process. 

 Na. Nasal-ring cartilage. 

 N/. Nasal fossa. 



0. Optic foramen (inner). 



O'. Optic foramen (outer). 



O". Optic foramen in sclerotic. 

 Ora. Oculi-motor foramen (inner). 

 Om'. Oculi-motor foramen (outer). 



On. Posterior opening of orbito-nasal canal. 

 On'. Anterior opening of orbito-nasal canal. 

 On". Orifice of canal in front of orbito-nasal canal. 



Op. Occipital process. 

 P. Parietal fossa. 



P'. Cartilaginous process underlying nasal fossa. 



Pa. Patheticus foramen (inner). 



Pa'. Patheticus foramen (outer). 



Pol-5. Pharyngo-branchial cartilages. 



Po\ Palato-basal depression. 



P/. Pre-frontal fossa. 



Pa. Post-orbital groove. 



VI. Foramen of exit for palatine branch of facial nerve. 

 Pto. Parietal eminence. 



Po. Post-orbital process. 



Pp. Palato-basal process. 



