5o6 Journal of Comparative Neurology. 



probably metasyphilitic affection may begin with the optic nerve 

 and stay there, or may begin in the leg segments (shooting 

 pains, etc.) or rarely on the ulnar side of the arms, and only 

 very rarely on the pneumogastric (gastric crises). Edinger at- 

 tempts to explain this by differences of resistive power in the 

 various segments on the ground of his ' Ersatz-theorie ' (see his 

 article in Volkmann's Vortrage). 



The following is a summary of the diseases in question, 

 closely following the outline given by me in an article published 

 in 'Medicine,' May, 1896. 



I. Poisons which cause segmental di^tcXXons with almost 

 exclusive involvement of the motor side. 



1. Acute anterior poliomyelitis, or acute infantile paraly- 

 sis : degeneration of the anterior-horn cells, motor fibers and 

 muscles for one extremity, rarely for two, practically never in- 

 volving the afferent side, and hardly affecting the supra seg- 

 mental apparatus. (Striimpell's acute encephalitis is, to judge 

 from the analysis by Oppenheim, hardly proven to belong to 

 the primary affections of nervous elements, but would require 

 further study from this point of view). 



2. Lead poisoning : affecting largely the motor elements 

 belonging to the musculo-spiral nerve, more rarely those of the 

 ulnar and median nerve ; in rare cases only the supinators and 

 biceps, brachialis internus, and deltoid are involved (Remak's 

 type). It rarely affects the peroneal nerves. In very severe 

 intoxication, the paralysis may become generalized, and espe- 

 cially in these cases involvement of supra-segmental parts — en- 

 cephalopathia saturnina — is marked, the minute anatomy of 

 which is not clearly known, and the accurate study of which is 

 difficult on account of the existing disorder of the 'lowest 

 level,' i. e. the segmental motor neurones. 



3. Apparently we should be forced to put down here the 

 cases of Landry's paralysis. The usual t}'pes have been found 

 to be largely polyneuritis ; many of them also showed sensory 

 disturbances and reaction of degeneration of the muscles. 

 Thus an analysis of the cases leads one to the conclusion that 

 Landry's paralysis is a symptom-complex occasionally met with 



