THE NERVOUS SYSTEM. 211 



infiltrated were abundant in both the grey and white 

 substance of all parts of the cord, the distribution varying 

 much. The infiltration was in the form of ramifying 

 tracts corresponding to the course of the vessels and was 

 probably leucocytal. Some of the nerve-cells were very 

 granular, others surrounded by lymphoid cells. Some had 

 a granular centre and ill- defined boundary, and in some 

 many vacuoles encroached on the protoplasm ; these 

 vacuoles are possibly of some pathological significance. 

 A similar infiltration of the medulla and cerebellum, but 

 slighter, was found. In each case the effect of section of 

 the spinal cord was tried ; in the slighter case the move- 

 ments continued for a few moments after pithing, in the 

 other artificial respiration was kept up and no movements 

 occurred in the parts below the section. This is not in 

 accordance with the results of other similar experiments. 

 The only morbid appearance common to the two cases 

 was change in the nerve-cells of the cord ; this is probably 

 primary, the vascular changes and infiltration being secon- 

 dary ; whether the infiltration results from vascular dis- 

 turbance or is due to overaction of the cells is uncertain. 

 This detailed account of a careful examination of the cen- 

 tral nervous organs in chorea by competent observers, arid 

 with elaborate modern appliances and methods, fills a 

 gap in the pathology of the dog. Its result is not alto- 

 gether satisfactory ; it amounts to the conclusion that in 

 chorea we find granular degeneration of the nerve-cells, 

 atrophy of the central organs. The cessation of function 

 in these cells may be evanescent, due to something dele- 

 terious in the blood, for Dr. Harley has produced chorea 

 artificially in the dog by administration of the alkaloid 

 cryptopia ; the clonic spasms came on about half an hour 

 after administration of the drug and ceased only when it 

 was eliminated. Treatment must be essentially directed 

 to supporting the system of the animal and determining 

 the flow of blood to the brain and spinal cord. The latter 

 process in acute cases may be accomplished by blisters 

 along the course of the spine, or the insertion of a seton 

 either in the region of the loins or in the poll. Asafcetida 



