284 O. VAN DER STRICHT 



the outer rods of Corti and the neighboring outer hair cells, and 

 between the three rows of outer acoustic elements. The}^ contain 

 fluid and are traversed by the phalanx processes of the cells of 

 Deiters, intercommunicating through clefts between the sensory 

 elements, and communicating with the tunnel space through 

 interstices between the outer pillars. The view taken by Nuel, 

 that they communicate with the lumen of the cochlea "par 

 I'entremise de lacunes en fonne de rames de la mambrane 

 reticulaire," must be regarded as erroneous. 



The development of the tunnel space between the two spiral 

 rows of rods of Corti appears to be verj^ difficult of observation. 

 Indeed, most authors, referring to its appearance in embryonic 

 material, state that it originates in the form of a narrow cleft 

 between the inner and outer pillars, but give no details con- 

 cerning the significance of this primitive interstice. Is it inter- 

 cellular or intracellular? From what source is derived the fluid 

 contained within the cleft? Those observers who clearly specify 

 that the space appears between two neighboring pillars, as do 

 Gottstein (72), Retzius ('84), Vernieuwe ('05), N. Van der 

 Stricht ('08), and Hardesty (.'15), give no explanation as to the 

 origin of its fluid. Alluding to the development of the space 

 in rabbits two daj^s after birth, Retzius states (p. 303) : 



Von besonderer Bedeutung ist nun die enge Spalte, welclie zwischen 

 den beiden Pfeillerzellen reichen, ungefahr in der Mitte der Zellenhohe, 

 nach oben vom spiralen Nervenbiindel entstanden ist und den Anfang 

 des Tunnelramiis dai*stellt; diese Spalte ist in der Basalwindung — wo 

 indessen noeh eine geringe Neigiing der Pfeillerzellen nach aiissen hin 

 vorhanden ist — noch viel weiter entwickelt, und man sieht hier deutlieh, 

 dass die durch Einziehung (Verdtinnung) der beiderseitigen Pfeiller- 

 zellen entstanden ist. Gleichzeitig ist aber auch die Anlage der Pfeiler 

 in der Zellen als helleglanzende Streifen nunmehr wahrnehmbar. Nach 

 aussen von der ausseren Pfeilerzellenreihe sieht man deutlieh auch die 

 Anlage der Nuelschen Raums. 



According to Vernieuwe, the timnel space is produced by the sep- 

 aration of the bases of the two pillar cells, due to elongation of the 

 pillars, increase in size of the nuclei, and chiefly by the extension 

 of the subjacent basilar membrane. Referring to the trend of 

 the spiral organ of Corti towards the axis of the cochlea, Har- 



