CHAPTER x'lV. 

 DISEASES OF THE NEEYOUS SYSTEM. 



General causes. Epilepsy. Falling Sickness. Chorea, St. Vitus's Dance, 

 St. Guy's Dance. Vertigo, Megrims in horses. Lock-jaw, Trismus, Teta- 

 nus. Convulsions, Fits. Sleepy Staggers, Coma Somnolentum. Apo- 

 plexy. Inflammation of the Brain, Phrenitis, Encephalitis, Cerebral Men- 

 ingitis. Inflammation of the spinal cord. Myelitis, Spinal Meningitis. Ep- 

 idemic Cerebro-splnal Meningitis, Cerebro-spinal P'ever. Enzootic Myelitis 

 in sheep. Trembling, Hydro-rachitis. Paralysis. Loss of sensation or 

 voluntary motion. General Paralysis. Paraplegia, Palsy of the hind limbs. 

 Hemiplegia, Palsy of one lateral half of the body. Facial Paralysis. Other 

 local palsies. Stomach Staggers and Acute Lead Poisoning. Sun-stroke. 



The frequency of these affections bears some relation 

 to the development and activity of the great nerve centres 

 and especially the brain. They are often symptomatic 

 of other diseases, the irritation being conveyed along the 

 nerves to the nerve centres so as to derange their func- 

 tions ; at other times they have their origin in these cen- 

 tres themselves. Among common causes may be named : 

 exposure to intense heat or cold, especially with a dry 

 parching atmosphere ; excess of Hght ; deranged or ex- 

 cited circulation, as in loss of blood or plethora, obstacles 

 to the return of blood from the head, by the jugular veins, 

 or imperfect supply from thickening of the cranial bones ; 

 the influence of poisons, pressure, etc. ; severe overexer- 

 tion ; digestive, hepatic and urinary disorders, and para- 

 sites. 



EPILEPSY. FALLING SICKNESS. 



This is seen in dogs, cattle, horses and pigs in about 

 the order named. It usually exists independently of any 



