=Psychologic Stages.=—There are three rather distinct psychologic stages in catarrhal deafness. The first, the period in which most patients refuse absolutely to admit that they are deaf even to the aurist upon whom they call for treatment. They insist that they hear perfectly if people would only speak distinctly. This is partially true, because up to the third stage of deafness the voice can be fairly well heard if people would only articulate clearly. In the second stage patients admit that they don’t hear well, but insist that they are going to recover normal hearing and often resort to various kinds of injurious treatment. In the third stage they give up all hope of ever regaining their hearing, become morose, and avoid company. These psychic stages do not always correspond with the pathologic stages given above. =Diagnosis.=—The external auditory meatus, drum membrane and ossicular chain, constitute the apparatus whose function is that of conduction of sound waves to the perception apparatus of the inner ear. The function of the conduction apparatus varies inversely with the progress of pathologic change in these structures. The perception apparatus, the structures of the inner ear, are not necessarily affected by middle ear pathology, but on the other hand, sounds transmitted by bone conduction not only seem louder but they last longer because the “escape of the excess” of sound thus transmitted is hindered by deficient conductive mechanism. This explains why such persons hear well by telephone and why the tuning fork, whose base is held to the mastoid (provided there is no nerve affection) may be heard for a greater time than normal. Likewise the prong of the vibrating tuning fork when held near the concha is heard for a shorter time than normal, because of the deficient function of the conduction mechanism. Tuning forks are known by their number of vibrations per second, such as 16, 32, 64, 128, etc. Three or more forks are required to make an accurate measurement of the conduction and perception functions—a low fork about a 32, for the low tones, 128 or a 512 for the medium tones and a 2048 for the high tones. A good set of forks should be selected and standardized, i. e., the normal bone and air conduction of each fork determined by testing it on a number of persons whose hearing is known to be normal. For the general practitioner who cares only to get a general idea of the extent of the pathology, one fork of medium pitch such as a 128 or 512 will be sufficient. To measure the function of hearing, the fork is set into maximum vibration, its base held against the mastoid and the patient is asked to state when he no longer hears it. This length of time in seconds is recorded as “bone conduction.” The fork is then held near the concha and the patient again states when he does not hear it. This length of time in seconds is recorded as air conduction. Normal Hearing