DETERMINATION OF SOUND DIRECTION.

Among the many functions that have been attributed to the semicircular canals, that of the determination whence sounds proceed, has received the support of some physiologists. Though the majority have strenuously denied this as one of their functions, some late experiments would seem to point to these canals as not wholly unconcerned in the perception of acoustic space. Their peculiar arrangement, occupying as they do three dimensions of space, is most seductive in the formation of theories bearing on our conception of space relationships. The objection was long ago pointed out that in the quad-rumana, which led a more or less topsy-turvy sort of a life, the respective relationship of these canals to the three dimensions of space must be constantly changing, and hence, in these creatures at least, they can have but little effect in the determination of space direction. Many fishes have only one or two semicircular canals.