It is not easy to give a short and definite answer to this question. No special examinations of the essential parts of the ears of eminent musicians have been made, so far as we are aware, and as yet few of the brains of this class of men. It is, however, practically certain that there is a brain development peculiar to the born musician, and that this, whatever else it may be, involves a special excellence of the auditory path within the brain, rather than any unusual development of the essential parts of the ear. The individual who is a musical prodigy has, without question, _a more perfect connection_ established between his auditory apparatus, in the widest sense of the word, and those muscular mechanisms employed in the execution of music, whether vocal or instrumental, than is the case with the average man. Usually, with this goes a wide series of brain associations or connections, we may presume, between the auditory tracts and other regions, for without this it is difficult to explain temperament and artistic perception. That they are not necessarily associated, however, is clear from the fact that some have a high degree of executive ability and little real artistic development. It must never be forgotten, however, that whatever else music may be, it is essentially and primarily a sensuous experience. The one who enjoys music must feel its sensuous charm, and the artist who furnishes that which is enjoyed addresses himself primarily to our auditory mechanism. Executing music is hearing music, and enjoying music is hearing music, though both may involve much more than this, and herein individuals must differ greatly, owing to education, past experience, etc.; but all who have the power to really appreciate music must be capable of the sensuous enjoyment of tones. In this all everywhere find something in common; often that which we enjoy is of the most varied nature. One thing is certain: those connections between the hearing and the motor processes we term singing or playing should be made early in life, if they are to reach that degree of facility and general excellence essential to success. We think there is good reason to begin voice-production early, as well as the practice of an instrument, though we do not maintain that the argument is as strong in the one case as in the other. That the "ear for music" may be well developed, in the sense that one may know perfectly what is correct in time and tune, without the power to execute well, there can be no doubt, as witness the case of many composers, but the reverse does not hold. There can be no doubt that _the nervous impulses that pass from the ear to the brain are of all sensory messages the most important guides for the outgoing ones that determine the necessary movements_.