Nerve deafness is not an uncommon disease. In my cases of deafness there has been some involvement of the labyrinthine structures or auditory nerve in 27% of the cases examined. I think the reason for most authors putting the percentage of nerve deafness much lower than this is because of inexact methods of diagnosis. The above percentage is based upon the actual measurement of nerve force. See measurement of nerve force under non-suppurative otitis media above. A careful study of cases by the method of actual measurement of nerve force, shows that there are two distinct forms of nerve deafness. In one there is only a deficient function of the structures of the labyrinth, due perhaps to some perverted physiologic function, and this form we may call auditory nerve deficiency. The other form of nerve deafness, due probably to an actual degeneration of the nerve or its end organs in the labyrinth, may be properly known as auditory nerve degeneration. =Auditory Nerve Deficiency.=—A study of our case reports shows that in 64% of the cases in which the nerve force was 16-30 or higher (more than half) favorable results were obtained, provided that there was no complicating labyrinthine affection. These cases have been classed as “nerve deficiency” and the pathology as functional. A favorable prognosis (64%) may be offered. Example of tuning fork findings: Fork 32 64 128 512 2048 4096 B. C. 18 20 20 20 10 A. C. T 50 60 60 40 20 In addition to the tuning fork findings the voice and watch test will be reduced to from one-tenth to two-thirds normal. The patient often complains of itching meati and dry nares. There are usually no signs or symptoms of labyrinthine affection. =Treatment.=—The treatment consists of local treatment to the nasopharynx, tubes and meati as described under the treatment of chronic otitis media. Everything should be done to build up the patient’s general health and improve the local nutrition. It is highly essential to search the entire system for sources of focal and general infection. Auto-intoxication from chronic gastro-intestinal disease was found in 90% of our cases. Any treatment therefore that will restore normal gastro-intestinal function is indicated. Recently we have had some excellent results from colonic irrigation and the proper adjustment of diet in such cases. Any source of focal infection must of course receive proper attention.