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THE NERVOUS SYSTEM. 



Most common are degenerations of the pyramidal tracts from haemor- 

 rhages into the sensory-motor region of the cortex, or from haemorrhages 

 into the internal capsule (lenticulo-striate artery). Hemorrhages in- 

 volving the optic centres or the optic fibres lead to degeneration in the 

 optic tracts. Haemorrhages into other portions of the brain, by destroy- 



ing commissural cells or interrupting their fibres, lead to degeneration of 

 intracrauial fibre tracts. 



Haemorrhage in the Spinal Cord is much less frequent than in the brain, 

 but may occur either as capillary apoplexy or as larger apoplectic clots. 

 Capillary haemorrhages, similar in appearance to those of the brain, may 

 occur as the result of injury, or near areas of softening or tumors, or may 

 accompany severe convulsions, as in tetanus. Apoplectic clots, which 

 are comparatively rare in the spinal cord, are usually small, commonly 



