NERVOUS SYSTEM. 105 



young person, what favourable termination often hap- 

 pens? 



JZ. The clot is encysted, absorbed, and the cavity final- 

 ly obliterated by an adhesion of the sides of the cyst. 



Q. When are bloody effusions found in the brain? 



#. They are found in the substance of the cerebral 

 mass, not in the exterior, nor in the ventricles. 



Q. What fluid is usually found in the ventricles and on 

 the external surface of the brain? 



#. Serum; and when this effusion is superficial, its 

 source is the pia mater, but the serum in the ventricles is 

 always from the arachnoid. 



Q. What disease does serous effusion in the brain con- 

 stitute, and what in the spinal canal? 



*#. In the brain it is termed hydrocephalus; in the spi- 

 nal column it is hydrorachitis. 



Q. What is the pathology of those head-aches, which, 

 in gastric affections, so severely afflict the forehead and 

 one eye? 



.#. They are sympathetic affections of the mucous mem- 

 brane of the frontal sinuses, and of the mucous membrane 

 on the eye-ball. 



Q. How do you divide alienation of mind? 



%#. Into the congenital and acquired. 



Q. What causes the congenital alienation ? 



*#. Organic derangement. 



Q. What hardening of the brain is most common? 



#. A white fibrous hardening in the white substance. 



Q. What alteration in volume does the brain undergo? 



#. It diminishes, but never morbidly enlarges in its 

 volume. 



Q. What are the diseases of the nerves? 

 14 



