286 LAMINA SPIRALIS OF THE COCHLEA. 



and Claudius. The membrane of Corti extends, as Claudius 

 has stated, to the outer wall of the cochlea, and the large 

 cells between it and the lamina spiralis have extremely 

 thin walls, and transparent contents, so that they resemble, 

 when pressed together, an areolar network. Portions of 

 the rods were also occasionally seen curled up, and as ob- 

 served by Claudius, attached by their expanded extremi- 

 ties, in series, to the membrane on which they lie. The 

 detection by Kolliker of the connection of the nerve-fila- 

 ments with the rods is, after the discoveries of Corti, the 

 most important recent addition to our knowledge of the 

 structure of the cochlea. Even in the ordinary view of the 

 structure from the vestibular aspect, the nerve-filaments may, 

 without much difficulty, be observed to disappear at or in the 

 central extremities of the rods. Their inner extremities do not 

 correspond, as Kolliker has correctly observed, to the outer 

 ends of the " dents apparents," but to the intervals between 

 the latter. Kolliker holds, on chemical as well as anatomical 

 grounds, that the rods of Corti are true terminations of the 

 cochlear nerves peculiar forms of the ultimate nerve-fibre. 

 He believes Corti's opinion to be erroneous, that they are 

 developments from the membrane on which they lie, and that 

 they constitute a physical apparatus. Notwithstanding K61- 

 liker's opinion, it may be safely asserted that the rods of Corti 

 present a configuration and aspect which distinguish them in 

 the most marked manner from any form of the nerve-filament. 

 The peculiar flattened articulated form, the variable breadth, 

 and, as pointed out by Claudius, the alternate arrangement of 

 the proximal and distal segments of neighbouring rods ; and, 

 lastly, the elasticity, slight, though marked, which they possess, 

 indicate that they are not true nerve-structures. Without 

 stating the nature of the function he supposes them to per- 

 form, Corti believes that the rods move like a series of ham- 

 mers. Harless conceives that they act as dampers by pressing 



