THE HEAD AND NECK. 



123 



4. Superior petrosal, in the petrosal margin of the tentorium cerebelli. 



5. Inferior petrosal, at the inner posterior border of the petrosa. 



6. Occipital, in the attached margin of the falx cerebelli. 



7. Cavernous, external to body of the sphenoid bone. 



8. Circular, in diaphragma sellae, around the pituitary body. 



9. Sigmoid, on the inner part of the mastoid process. 



10. Transverse, connecting the inferior petrosal ; also called basilar. 



1 1. Straight, at junction of falx cerebri and tentorium cerebelli. 



The arteries of the dura mater are the great, small, anterior, and posterior 

 meningeal ; the anterior and posterior ethmoidal ; and branches of the occipital 

 and ascending pharyngeal. The nerves to the dura mater are the sympathetic, 

 ophthalmic, hypoglossal, the pathetic, and the Gasserian ganglion. 



As you have seen in your dissection, the dural sinuses are between the two 

 layers of the dura mater. They are for the reception and transmission of venous 



Falx cerebri 



Choroid plexus 

 Veins of Galen 



Tentorium 

 cerebelli 



Lateral sinus 



CORPUS 

 DENTA TUM 



CA UDA TE 



NUCLEUS 

 LATERAL 

 VENTRICLE 



Superior petrosal 



sinus 

 MASTOID ANTRUM 



Lateral sinus 

 MASTOID PROCESS 



FIG. 83. CORONAL SECTION OF THE HEAD PASSING THROUGH THE MASTOID PROCESS. 

 (From a mounted specimen in the Anatomical Department of Trinity College, Dublin.) 



blood from the brain. The sinuses are lined by endothelial cells, continuous 

 with the lining of the veins. 



The arachnoid membrane you will know by the glistening appearance it 

 gives the brain. Externally it is in relation with the subdural space ; internally 

 with the subarachnoid space. 



Where is the subdural space located and what does it contain / 



It is located between the dura mater and the arachnoid membrane, and con- 

 tains a small amount of fluid. Call this fluid subdural. 



The subaracJmoid space is wJicrc located and contains what / 



It is located between the arachnoid membrane and the pia mater. It contains 

 the greater part of the cerebro-spinal fluid. Call this fluid subarachnoid. 



Docs the subdural fluid communicate with the subarachnoid fluid ? 



No ; the two are separated from each other by the arachnoid membrane. 



