RAIA. 



325 



anterior end it is produced into a pointed rostrum and at the 

 posterior end is a large hole, the foramen magnum, leading 

 into the cranial cavity. On either side of the foramen 

 magnum is a large occipital condyle or facet. At the base of 

 the rostrum on each side is an olfactory capsule opening 



Fig. 232.— Lateral View of Skull of Skate (Natural Size). 



{Adnat.) 



Palatoquadrate 



Mandible. 



Spiracular 

 Cartilage. 



Hyoid. 



2nd Branchial 



Nasal Capsule. 



_- — Optic Foramen. 



Orbit. 



Foramen for 

 V.andVIL 



Auditory 

 Capsule. 



Hyomandibular. 



3rd Branchial, 



4th Branchial, 

 5th Branchial. 



ventrally and containing the nasal sac. On either side of 

 the posterior region is a large auditory capsule containing 

 the auditory sac. The lateral walls of the cranium bound 

 the orbit and have several foramina for transmission of the 

 cranial nerves. 



