460 NERVOUS SYSTEM. 



The general changes are indicated by signs precisely similar to 

 those so common in horses with dropsy of the ventricles (general 

 depression, inability to back, long intervals between the prehension 

 of successive mouthfuls of food, sudden cessation of mastication, etc.), 

 by an impulsive or automatic gait, and by the assumption of strange 

 attitudes (kneeling down in front, etc.). When at rest the animals 

 appear to be in a state of continual torpor. 



Special symptoms sometimes occur, which enable the seat of the 

 injury to be localised in more or less exact fashion. These symptoms 

 affect the vision (amblyopia, amaurosis, strabismus, nystagmus), general 

 sen&ilnlity (hyperii-sthesia, anaesthesia, etc.), and the power of move- 

 ment (total, partial or crossed hemiplegia, want of co-ordination of 

 movements, etc.). 



Trifling stimuli almost always lead to marked and even epilepti- 

 form attacks. 



The diagnosis of cerebral tumours is very difficult, particularly 

 when attempts are made to indicate their exact seat, but that of 

 other cerebral lesions is somewhat easier. 



The prognosis is very grave, and in the case of domestic animals 

 nothing can be done. In the ox intra-cranial operations are diffi- 

 cult, by reason of the presence of the sinuses which obstruct the 

 approach to the brain cavity ; economically surgical treatment is 

 seldom advisable. 



INSOLATION. 



Insolation is an exceptional accident in animals of the bovine, 

 ovine, or porcine species. If at liberty these animals move about, 

 and always seek shelter when the sun is fierce. If, on the con- 

 trary, they are harnessed and kept standing for long, exposed to the 

 full midday sun during June, July or August, they may suffer from 

 insolation. 



During the International Cattle Show attached to the Exhibition 

 of 1900 in Paris, a considerable number of cases of insolation occurred 

 in animals of one class, exposed to the full midday sun, in an ill- 

 ventilated spot. The other classes only received sunlight from the 

 sides, and in them not a single case occurred. 



Death may follow in a few hours ; it is difficult to say precisely 

 how it is brought about, but it is always accompanied by congestion 

 of the cerebro-spinal centres and general blood stasis. 



The symptoms of the development of insolation occur very rapidly. 

 In animals of the bovine species there is accelerated respiration, which 

 soon amounts to dyspncea. The mucous membranes then become 

 cyanotic. The animals attacked seem anxious, although not agitated, 



