Diseases fff the Nervous System. 229 



bably also of the nutrient vessels, in which any sudden 

 pressure from determination of blood disarranges the 

 functions of the sensorium, or, as in many fatal cases, 

 rupture occurs, followed by extravasation. Usually the 

 disease appears without warning, but sometimes it may 

 be preceded by dullness and want of co-ordinate power. 

 In sudden attacks the animal falls helpless, insensible, 

 and paralysed. The only signs of life are those of respi- 

 ration and circulation, the former being stertorous, and 

 the eyes are wide open and staring. Urine and faeces 

 pass involuntarily, and the legs are mobile, the muscular 

 system being flaccid. Sometimes consciousness is partly 

 retained, when the animal injures himself in convulsions, 

 during which the head is drawn backwards, and the 

 croup forwards and upwards. These attacks of quies- 

 cence and convulsions alternate until death closes the 

 scene. 



Treatment is usually hopeless. Bleeding only during 

 the comatose state. Strong aperient, No. 3, with enemas ; 

 strong embrocations to the spine ; internally, belladonna 

 during brain congestion, afterwards strychnine. Re- 

 covery is generally little more than partial and delusive. 



DISEASES OF THE SPINAL CORD AND ITS COVERINGS. 



PARALYSIS. We have already noticed this disease as 

 it occurs in connection with, and as a symptom of, other 

 affections. It remains to consider it as dependent upon 

 some lesion of the spinal cord or the nerves which 

 originate in it. Loss of power is the distinguishing sign, 

 having its origin in disease or injury of the cord, and 

 when such extends to both sides it is known 'as paraplegia; 

 if one side only is affected it is then spoken of as hemi- 

 plegia. Loss of power in isolated parts, also in a series 

 or number of members would be understood by the term 

 paralysis. 



ACUTE PARALYSIS, or Spinal Meningitis^ is denoted 

 sometimes by gradually developed paralysis ; in other 

 instances it is preceded by cramps, spasms, and convul- 

 sions, and it may come on suddenly, when fracture or 

 displacement of one or more segments of the vertebrae is 



