170 Irving Hardesty 



when the series comes to lie flat on the slide. However, if this were true, 

 one would expect all of the shafts to be curved, whereas those in the 

 middle of each group are usually straight. Again, if the shafts stand 

 straight and equidistant during life, noticeable depressions in the sur- 

 face of the phalanges opposite the spaces between the groups would 

 probably result from the bending of the shafts in forming the grouping. 

 In all the preparations, the outline formed by the cohering phalanges 

 appeared straight. Further, in the grouped conditions shown in the 

 preparations, the granular protoplasm dispersed between the rods ap- 

 peared continuous throughout the smaller spaces between the rods of 

 each group, but in the spaces between groups it appeared above and 

 below with a thin film along the sides of the bounding rods, leaving a 

 definitely bounded vacant space in the center (p.. Fig. 12). In the 

 split shown in Fig. 13, the upper area of this protoplasm appeared split 

 also-. Since this preparation came from a cochlea fixed in Zenker's fluid, 

 the protoplasm must have been hardened while in position in the 

 cochlea and therefore was firm enough to be broken, as shown when the 

 rod-series was split by the teasing process. 



Whether equidistant or grouped in life, the preparations suggest an 

 anatomical arrangement which may increase the functional possibilities 

 of the organ. As shown by Joseph, '00, and by Held, '02, and as shown 

 in Fig. 12, the rods proper consist of bundles of longitudinally placed 

 fibers held together by a seemingly hyaline matrix, and therefore may 

 be distinguished from the granular protoplasm distributed between the 

 rods and forming the foot cells. From all appearances, the rods are 

 relatively rigid, the outer more so than the inner series, and their pres- 

 ence is generally conceded as serving for the support of the neuro- 

 epithelium at each side. If they are grouped during life, then the two 

 phalanges which come together opposite the larger spaces between the 

 groups (a., Fig. 12), might be less resistant to vertically applied force 

 than would the phalanges of the rods of the middle of the groups, b, 

 and thus, also, would the hair cells immediately supported by these 

 phalanges be held in varying degrees of rigidity against the impact 

 of the tectorial membrane. On the other hand, a separation of the 

 rods, as shown in the groups, into straight and equidistant relations 

 would produce slight bulges in the outline of the coherent phalanges, 

 and thus, if the rods are straight and equidistant during life, this condi- 

 tion probably results in hair cells at intervals standing higher than 

 others and more apt to be stimulated by slight undulations of the tec- 



