PROPORTIONS OF THE TECTORIAL MEMBRANE 9 



('08) represented a thin section after paraffin in which the membrane 

 was cut in a plane parallel to but splitting Huschke's teeth. It showed 

 the fibers near the teeth necessarily cut across, since they curve apex- 

 ward toward the surface of the teeth, while the plane of section through 

 the body of the membrane was more or less parallel in places with the 

 course of the fibers. That the fibers in this section appeared as'washed 

 together, cohering to each other in anastomosing bundles, was ex- 

 plained by me as due to shrinkage and resultant agglutination. But 

 Prentiss interprets this figure as showing his chambered structure, 

 though the sections of the chambers he sees (the meshes of the appar- 

 ent reticulum of bundles) vary from sizes for smaller than sections of 

 the cells supposed to produce them could be, and the very various 

 shapes of the meshes are questionably similar to what would be the 

 shape of the cells so sectioned. Prentiss' figure 8, a section of the 

 membrane similar to m}^ figure 9, shows some of the larger meshes (sec- 

 tions of his chambers) about ten times the size of the smaller meshes. 

 The cells of neither of the epithelial thickenings or ridges vary so in 

 size. His section merely indicates even more agglutination than mine. 

 As to the endolymph filling his chambers, Prentiss states that I "could 

 not demonstrate by special stains the presence of a matrix which 

 would hold the fibers together." The presence of the seemingly gelat- 

 inous or soft keratinous matrix, in which the fibers are embedded, 

 seemed to me one of the most evident features of my preparations of 

 teased tectorial membranes, and its presence and apparent character 

 was described by me as well as by others previously. That I was un- 

 able to determine by stains a definite micro-chemical character for it 

 is true. 



I described in my teased preparations from the pig a structure which 

 I called an "accessory tectorial membrane." Prentiss states that this 

 probably represented the reticular membrane or lamina of the spiral 

 organ stripped off in the teasing. Whether this structure is an acces- 

 sory membrane or not, I have found that it likewise appears on the 

 basal surface of the membrane of the adult hog and in places not torn. 

 Prentiss' statement indicates first, that he has never seen it at all in 

 his 'dissections' and second, that his idea of the lamina reticularis 

 is rather pecuHar. 



My perhaps unnecessarily tedious experience in trying to determine 

 the normal character of the tectorial membrane and in trying to get 

 sections of it showing this character would lead me to suggest it rather 

 impossible to get normal preparations after fixation with osmic acid, 

 whose power of penetration is remarkably poor, or even with vom 

 Rath's fluid, and to get normal appearances would be certainly impos- 

 sible after decalcifying with 5 per cent nitric acid before embedding. To 

 me, all of Prentiss' figures drawn from the actual specimens show consid- 

 erable shrinkage, his figures 5 and 6 less than the others. In his figure 9, 

 the distortion of the tectorial membrane, outward and out of shape 

 is very evident. In his figure 10, given as representing the apical 

 coil of a pig at about term, the outer edge of the membrane is badly 



