FEOG 213 



auditory capsule cartilaginous? If so, what is 

 the relation of this part to the pro-otic bone? 

 Attached to the outer edge of the pro-otic and 

 extending downward to the posterior end of the 

 upper jaw find the squamosal bone. "What is 

 its shape ? What is its relation to the tynapa- 

 num ? Examine the cartilaginous ring, the tym- 

 panic ring, upon which the tympanum is 

 stretched. What is the relation of the ring to 

 the squamosal bones attached to the under sur- 

 face of the tympanum? Find the columella 

 auris. What is its structure ? Shape ? To what 

 part of the tympanum is it fastened ? Trace the 

 columella to its inner end, which closes the open- 

 ing or fenestra ovalis in the auditory capsule. 



In carefully prepared skeletons look for a car- 

 tilaginous rod, the styloid cartilage, running 

 from the pro-otic to the hyoid. bone. Examine 

 the roof of the skull and find a pair of bones, 

 fronto - parietals, extending forward from the 

 exoccipitals and pro-otics. What is their shape ? 

 How far forward do they extend ? What is their 

 relation to the cranial cavity ? Examine the 

 sagittal suture, along which these bones are 

 united. 



At the anterior end of the fronto - parietals 

 look for the sphenethmoid or girdle bone. 

 Anterior to the latter is a cartilaginous structure 

 on each side of which is a nasal bone. What is 

 its shape ? In which direction does it extend ? 

 What is its position with regard to the fronto- 

 parietal? How is it connected to the latter? 

 How does it differ structurally from the sphe- 

 nethmoid ? In front of the nasal bones lie the 



