No. I.] THE VERTEBRATE EAR. 157 



the canal organ, leaving out of consideration the canal itself ; 

 but as I have already shown, the only unusual structure, or the 

 auditory club, present in the organ is without doubt an artifact, 

 produced by the transforming action of the reagents used in 

 preserving the larvae. 



Leydig (1850, 179) was probably the first author to connect in 

 thought the surface canals (knowing their structure) with those 

 of the ear. In this paper he calls attention to the similarity of 

 the so-called mucous canals with the ampullae of the ear, but 

 later he was inclined to consider the lateral line organs as 

 tactile organs possessing a function unlike all others, and which 

 he suggested might be a sixth special sense. 



The idea advanced by F. E. Schulze (254) in 1861, that the 

 lateral line organs were probably affected by the water waves 

 of longer wave lengths, and also by the movements of masses 

 of water, had the advantage of being specific ; and to-day the 

 mass of evidence sustains his view. 



Dercum (1879, 70 considered the sense organs of the lateral 

 line so similar to the maculae of the ears, that he applied the 

 term maculae laterales to the former, and instituted a com- 

 parison of parts between ear and lateral canals more detailed 

 than had previously been attempted. 



Emery first described the cupula terminalis in the lateral 

 canals of Fierasfer, and compared these structures with those 

 of the ear. 



Maysers views I have already partly given. The posterior 

 root of the VIII together with the recurrens superior form the 

 nervus lateralis. The second branch of the V supplying the 

 " Nervenhugel" is given off from the VIII. Mayser concludes 

 that while it will be impossible to state definitely that these 

 organs transmit sound waves, yet their function undoubtedly 

 falls within the province of the auditory sense still so incom- 

 pletely known. 



Bodensteiji^ (1882) went further and compared the lateral 

 canals with the membranous canals of the ear ; the endolymph 

 he found represented by the fluid in the lateral canal ; the bony 

 canal was present as the denser investment of the lateral canal ; 

 and he concludes that the lateral canal system is probably an 

 ontogenetically later appearing repetition of the auditory organ ! 

 1 Zeitschr, fur wiss. Zool. XXXVII, 1882. 



