Symptoms. 54]_ 



duration of the disease. Forced movements are sometimes ob- 

 served and they are, as a rule, in the nature of movements 

 either in circles, forwards or backwards. 



When the disease is not very extensive, and especially when 

 it involves portions of the brain remote from the cortex,* symp- 

 toms of a general nature may be insignificant or even absent. 



Focal symptoms occur very commonly, but owing to the 

 severe disturbance of consciousness they remain unobserved, 

 or at least they cannot be certainly recognized, save with great 

 difficulty. Paralysis is very common. In some cases it is total 

 hemiplegia (Storch), sometimes hemiplegia alternans (Leiser- 

 ing and Thomassen), and finally there may be paralysis of some 

 of the cranial nerves (ptosis, strabismus, fixed dilatation of the 

 pupils, paralysis of the optic nerves, of the muscles of mastica- 

 tion, the pharynx, tongue and larynx). Extension of the in- 

 flammation may lead to a varying amount of paralysis of the 

 whole body with irregular movements of the limbs ; dogs can in 

 some cases creep along on their bellies or if supported may be 

 able to walk. Lienaux believes that this kind of disturbauce is 

 due to disease of the cerebellum. He observed it in cases of 

 encephalitis due to distemper, associated with exaggeration of 

 the patellar reflexes and nystagmus. It has been shown that 

 it may also follow inflammation involving the cerebrum. When 

 the respiratory center is involved death soon occurs with symp- 

 toms of dyspnea. 



In the carnivora rolling movements are often o])served, and 

 especially in cases of encephalitis due to distemper (Fried- 

 berger & Frohner and Marek). These types of forced move- 

 ments are often associated with rotation of the head on its long 

 axis, and it is more rarely associated with deviation of one or 

 both eyes. The disease generally involves the peduncles of the 

 cerebellum or the neighboring tissues (see page 593). 



In distemper encephalitis after the disappearance of the 

 general spasms, and in some cases without these s>anptoms hav- 

 ing appeared at all, there are observed more or less rhythmic 

 clonic contractions of the muscles supplied by the facial and 

 trigeminal nerves, resulting from a local inflammation in the 

 neighborhood of the nuclei of these nerves. 



In cases of extensive disease of the cerebellum, cerebellar 

 ataxia is observed. An especially interesting case of this sort 

 was observed by Marek in a dog, in which there was an exten- 

 sive perivascular infiltration in the medullary layer of the 

 cerebellum, and at places also in the cortex, tlie animal being 

 the subject of distemper. 



As soon as the dog voluntarily innervates its muscles, trembling movements of 

 that part of the body set in. Thus a nervous shaking of the head was observed in 

 attempts to raise it. In making efforts to stand the animal fell over frequently, 

 while in standing position the toes were extended and great efforts were made to 

 maintain balance j these, however, were more marked during progression. During 

 movement the limbs were swung forward, sometimes with abduction and sometimes 

 with adduction and the feet were put down clumsily, and the animal soon fell either 

 on its side, or forwards or backwards. Every effort to defecate was promptly fol- 



Vol. 2—41 



