EXAMINATION OF THE NERVOUS SYSTEM. 201 



stantly contracted. It may occur for a minute or two, or may last 

 several days. Tonic clonic convulsions are the medium form of 

 the two conditions before described. A mild form of clonic con- 

 tractions is noticed in the original muscular twitchings. Trem- 

 bling and shaking convulsions seen in chills, fear, or sudden 

 cooling after heat. Epileptiform convulsions, or eclamptic con- 

 vulsions, are seen and extend over the whole body. In very 

 rare instances they may be restricted to one portion, such as the 

 head or neck. These generally come on suddenly and disappear 

 in a few minutes. They are generally seen in the early stages- 

 of distemper, in teething, in irritated conditions of the bowels, 

 or from noxious and poisonous food and from parasites; in cases 

 of pentastomum in the nasal cavities, in encephalitis, meningitis, 

 uraemia, and occasionally in acute ansemia; they may also occur 

 from some injury or irritation of the peripheric centres, and are 

 very prominent in epilepsy. Rhythmic twitchings are seen in 

 some muscular regions where the affected part of the body makes- 

 regular motions; for instance, in the muscles of mastication, in 

 the muscles of the chest during sleep, and also in the twitching 

 of certain limbs. They are very often mistaken for chorea, and 

 appear as a result of distemper or some disease of the brain. 

 They may also occur from disorder of the spine. These so-called 

 cataleptic attacks consist of a rigid and contracted condition of 

 all the muscles of the body, but are subject to passive movements. 

 Nothing is known concerning their etiology. Tetanic convulsions- 

 are tonic convulsions of the whole muscular system of the body. 

 They appear in tetanus and in some cases of poisoning (strychnine, 

 brucine, caffeine, etc.). A variety of these tetanic convulsions is- 

 observed in the so-called cases of eclampsia in bitches who are 

 nursing a litter. Forced irregular actions of the body, such as- 

 walking backward or in a circle, or the animal rotating on its own 

 axis, are seen as a rule in diseases of the cerebellum and in some- 

 cases of poisoning (cocaine). In rare instances we see, in the 

 above-mentioned, symptoms of " epileptiform attacks," which we 

 will refer to further on. 



Ataxia is due to disturbance of motility or an interference in 

 the coordination of muscular action. Animals are unsteady on 

 their legs, stagger from one side to another, and their action in 

 walking is irregular. Ataxia is undoubtedly found in some dis- 



