240 DISEASES OF TRUE INFECTION. 



diplococci or egg-sliaped corpuscles which could be cultivated in 

 blood-serum at 37°. Dodeswell found in the spine and medulla 

 a coccus, and Rivolta noticed a " coccobacterium lyssse." Aurep 

 produced a very poisooous alkaloid with the brains of 100 rabbits 

 (affected by furious rabies). 



JSTegri has found in the nervous system, brain and upper portion 

 of spinal certain bodies which he has described as parasites; 

 although a number of authorities question whether they can be so 

 termed. These bodies called "Negri bodies" vary greatly in size, 

 running from one to twenty-five microms, they also have great 

 variety in form, generally round or oval, more rarely elliptical, 

 and Marx has described them as also occurring in coarse«triangular 

 form. These protozoon-like bodies are found in the hippocampus 

 major and in the cerebellum in large numbers in the majority of 

 dogs that die of Babies; although a certain number of cases where 

 the animals have had a clear history of being bitten by another 

 rabid animal, and after the animal bitten was killed early in the 

 disease or shortly after showing the first symptoms, the "Negri 

 bodies" were not found. Numbers of observers since Negri's dis- 

 covery have confirmed, and also believe with him, that these bodies 

 are peculiar to this disease and that the presence of these bodies 

 in the brain of the dog prove positively that he died of the disease. 

 The hypothesis is now accepted by the majority of state and patha- 

 logical laboratories ; on the other hand a number of observers ques- 

 tion the advisability of accepting this theory, and at present while 

 the hypothesis is really in a state of evolution, still it can be used 

 as a means of diagnosing doubtful cases of rabies. 



Schuder, who opposes the theory of "Negri bodies," has made 

 filtrates of the virus and states that the diseaseiwas reproduced 

 equally by the filtered and unfiltered virus. 



A number of observers find the ganglionic cells have undergone 

 degeneration changes in dogs that die of rabies ; but if the animal 

 is killed before he dies or early in the disease, these changes are 

 not found. Metchnikoff found similar lesions in old dogs. 



Filtrates of the infected nervous tissue, when injected experi- 

 mentally by Babes and Bertarelli, caused emaciation and paralysis, 

 and finally death; but the subsequent injection of the infected 

 preparations of the nervous tissues of these animals which died 

 did not reproduce the disease. 



