. The Journal of laryngology and otology. fromfresh human and animal labyrinths. Its strongest support is the fact that it affords a clue to thefunctions of those intra-labyrinthine structures whose uses have forever been a matter of pure conjecture. It is a theory which is applicable to all the facts. It affords areasonable and acceptable explanation to the functions of the hair- 19-i The Journal of Laryngology, [April, 1914. cells tliemselves, of tlie tectorial membrane^ of the reticulate mem-brane, of the basilar fibres, and it throws an illuminating sidelightapon the nature of the so-calle
. The Journal of laryngology and otology. fromfresh human and animal labyrinths. Its strongest support is the fact that it affords a clue to thefunctions of those intra-labyrinthine structures whose uses have forever been a matter of pure conjecture. It is a theory which is applicable to all the facts. It affords areasonable and acceptable explanation to the functions of the hair- 19-i The Journal of Laryngology, [April, 1914. cells tliemselves, of tlie tectorial membrane^ of the reticulate mem-brane, of the basilar fibres, and it throws an illuminating sidelightapon the nature of the so-called spiral ligament. In the present preliminary communication I do not propose toproduce any evidence, either histological or experimental, uponwhich this theory is founded, but to state it briefly and dogmati-cally. (1) The hair-cells of the organ of Corti are the end-organs ofthe auditory nerve. They respond to the stimulus of sonorousvibrations in two ways—the body of the cell by contraction, thesensory hairs by sympathetic Fig. 1.—ffair-cells.—a, a. Eesting or soundless cells, b. Contracting orsound-adapted hair-cell. The lower pole of a contracting cell is darker andmore granular than that of a resting cell, and its nucleus is obscured,c. Hair-cell with hair bent down (from pressure of damper ?). (2) The contraction of the cell frees the hairs from the pressureof the tectorial membrane, which acts as a damper. The cellscontract until they are beneath the level of the reticulate mem-brane, whose function it is to prevent this heavy damper fromsinking down upon the contracted cell. (3) Sound vibrations reach any particular hair-cell or set ofhaix-cells by means of the fibre or fibres of the basilar membranewhich support them. (4) The so-called ligamentum spirale is in reality a muscle,and acts as the tensor of the basilar membrane. It is thus ableto not only induce and inhibit paracusis by locking and unlockingthe rods of Corti, but also to produce any degree
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