581 



The sensitiveness of fishes to vibrations causing sound-sensations 

 in man, has been proved by Piper, who derived actioncnn-ents 

 from the N. ootavus when the fisli-iabjrinth had been isolated, and 

 b}' Pakkkr, who at the action of sound saw a number of fishes gather 

 at one side of the basin. 



The Clupeides are vevy sensitive to vibrations. Would this perhaps 

 be due to the special direct connection these fishes have l)etween 

 air-bladder and vestibular)' apparatus? 



I should saj there are ample grounds for investigating if not the 

 view of E. H. Wkbkr, Nusbaum and Sidoniak and others, wiio see 

 in the organ of Wkbku a means to transmit vibrations which the 

 air-bladder receives from ont&ide, to the vestibulary apparatus, must 

 be preferred to that of Hasse. Bridge and Haddon, Guyénöt, who 

 wish to connect this organ with the hydrostatic function of the 

 air-bladder. 



Of course 1 do not for a moment lose sight of the importance 

 of the air-bladder as a hydrostatic organ of sense. 



In my opinion it is, however, quite possible that further investi- 

 gations will prove that the air-bladder also serves to receive vibra- 

 tions and that the organ of Weber has to transmit these vibrations 

 to liie |)erilympli of the vestibulary apparatus. 



LITERATURE 



(concerning all three inferior parts of tliis treatise). 



Baglioni S., Zur Physiologie der Schwimmblase der Fische. Zeitschr. f. algem. 

 Physiol. Bd. VIU, 1908: 



Beaufort, L. F. de, De zwemblaas der Malacopterygii. Akad. Proefscin-ift, 

 Amsterdam, 1908. 



BoEKE, J., Beitrage zur Kenntnis der motorischen Nervenendigungen. Intern. 

 Monalschr. f. Anat. u. Physiol. Bd. 28, Leipzig 1911. 



BoEK, S. DE, Die quergestreiften Muskeln erhalten ihre tonische Innervation 

 mittels (ler Verbindungsaste des Synipathicus (Thoracales autonomes System) Folia 

 Nenrobiol. Bd. 7. Haarlem 1913. 



Bohr, G., The influence of section of the vagus-nerve on the disengagement of 

 gases in the airbladder of fishes. Journ. of Physiol, vol. 15, 18i)4. 



Gharbonnel-Salle, L., Recherches experimentales sur les fonctions hydrostati- 

 ques de la vessie natatoire Ann. d. Sc. Nat. (Zoölogie), 1887. 



Chevrel, R., Sur fanalomio du systeme nerveux grand sympathique des Elas- 

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 1887 — 1890. 



Deineka, D., Zur Frage über den Bau der Schwimmblase, Zeitschr. f. Wiss. 

 Zool. Bd. 78, 1904. 



GuYÉNOT, E. Les fonctions de la vessie natatoire des poissons teleostiens. These 

 de la faculté de medicine de Paris, 1909. 



