Neuritis is common; it is easily recognized, yet few conditions are so often inadequately diagnosed. The trouble is not that the physician does not name the pathologic condition correctly but that he is too willing to be satisfied with the mere naming and thereat cease his investigations. It seems important, therefore, to summarize at this time the status of knowledge concerning the etiology of neuritis so that the cause in each case may be more correctly understood and the treatment more appropriate. During the last fifteen years epidemics of encephalomyelitis, the advancing knowledge of dietary deficiency, and new industrial poisons have all added valuable facts to aid in the understanding of neuritis.
Many textbooks give excellent descriptions of the different types of neuritis, but the material is widely scattered under various headings. Of the monographic studies the best are probably by Ross and Bury1 in 1893, by Harris2 in