No. I.] THE VERTEBRATE EAR. 85 



percipient structures. Although Schultze's observations were 

 accepted by competent authorities as correct, the older idea of 

 the presence of the auditory jelly was only slightly affected; 

 and while there was nothing in Schultze's observations to give 

 color to the view, it was held, however, that the auditory hairs, 

 although undoubtedly present, did not project into a lymph-like 

 liquid, but were received into canals or other openings within 

 the gelatinous mass later called a " cupula terminalis." The 

 cupula terminalis was thought to be a secretion of the non-hair- 

 bearing cells of the sensory area. This idea gradually grew, 

 and was extended to the covering structures of all the auditory 

 sense organs, which were variously termed the membranse tec- 

 toriae, otolithic membranes, or reticulate membranes. The 

 special term appHed by Lang to the gelatinous mass of the 

 ampulla was the cupula terminalis, and it was not until 1878 

 that the whole error was overthrown and the complete meaning 

 as well as the entire accuracy of Schultze's observations was 

 demonstrated for the ampullar sense organs. Hensen, to whom 

 we owe this important demonstration, worked single handed 

 against the most determined resistance on the part of his con- 

 temporaries, and it was only after several years' time, during 

 which he repeated his own observations and republished his 

 account with additional facts and evidence, that he forced those 

 of different mind to admit that their ideas of the relation of the 

 sensory hairs to the ampullar cavity were entirely erroneous and 

 that the microscopic preparations of the ear sense organs, which 

 they supposed fully proved their position, normal though they 

 seemed, were artifacts, creations of their own unconscious 

 efforts, which although made, it must be admitted, in most if 

 not all cases, with the express purpose of getting at the truth, 

 were none the less destructive of the truth and constructive of 

 false conditions and conceptions. 



The demonstration by Lang of a dome-shaped, striated (some- 

 times apparently homogeneous) mass resembling stratified jelly, 

 led him to publish his cupula terminalis idea, and the ease of 

 demonstration and apparent constancy of the structure after 

 ordinary histological preparation led off other workers only too 

 completely, until Hensen took up the subject and studied the 

 ampulla under conditions as natural as it was possible to obtain, 

 with the result already mentioned. 



