“…I If, on the other hand, we take a subacute case of post-vaccinal encephalitis for direct comparison-such as a most interesting case (Case XII), with survival for 108 days, as reported in Blackwood's (1944) Edinburgh series-we find that the encephalomyelitis heals by the ordinary processes of glial and mesodermal scarring and shows no resemblance whatsoever to incipient multiple sclerosis. Furthermore, some hundreds of non-fatal cases of acute disseminated encephalomyelitis of the post-exanthematous type have now been followed over a sufficient number of years (Kudelka, 1932;Kaiser and Zappert, 1937) to show that at least this variety never progresses to multiple sclerosis even though it is the commonest form of acute disseminated encephalomyelitis and the one which pathologically, by reason of its "myelinoclases" or partial softening of the white parenchyma, most nearly imitates multiple sclerosis.…”