516 SUMMARY OF CURRENT RESEARCHES RELATING TO 



lime-salts during the foetal life, but gradually loses them as the ear 

 begins to hear. The clinical evidence is even more convincing. It 

 should be recognised that the acoustic conduction, the molecular trans- 

 mission, has no direct importance in hearing, which is associated with 

 the freedom of molar oscillation in the suspended media of the ear. 

 The phenomena of audition are not acoustic, but are associated with the 

 hydrodynamic phenomena of the internal ear. Neither otoliths nor 

 acoustic conductivity have anything to do with hearing. 



Otoliths of the Frog.* — M. Marage, answering P. Bonnier, points 

 out that he reached two experimental results : — (1) That a liquid of 

 2-18 density was a very good conductor of sound ; and (2) that one of 

 the functions of the otoliths was to maintain the acoustic conductibility 

 as constant as possible. He did not argue from frog to man. 



That the otoliths are found in one region cr another does not affect 

 the fact of saline dissolution. The fact that the density of the fluid of 

 the ear increases as one goes down the animal scale, may simply mean 

 that, as the nervous system is less perfect, a better conductor of sound is 

 needed. As far as he is aware, quantitative analyses of the fluid of the 

 internal ear have not been made either during foetal life or after birth. 

 The clinical observations of Gelle are not admitted as relevant. Bonnier's 

 statement of what occurs in the internal ear during audition is quite 

 theoretical. Whether there are vibrations, or movements of fluid as a 

 whole, or simply differences of pressure, — all is theoretical, but Marage's 

 facts remain. 



Circulation in Spleen.f — Dr. F. Weidenreich has made a detailed study 

 of the course of the blood-vessels in the human spleen, and has found 

 that they display some remarkable peculiarities. An explanation can 

 be found only by comparing the spleen with the lymph-glands and the 

 haamolymph-glands recently investigated by Drunimond aud others. 

 The author considers that those organs of the body which give rise to 

 lymph-corpuscles can be arranged in a series: — (1) the hagmolymph- 

 glands, the least specialised of all ; (2) the spleen, which is intermediate 

 as regards specialisation ; (3) the true lymph-glands, which are the most 

 specialised. 



Reptiles of the Pacific Islands.* — Dr. F. Werner prefaces his account 

 of tho reptiles of the Schauinsland expedition with a discussion of the 

 distribution. The reptilian fauna of the Pacific islands is directly pro- 

 portional to the distance of the islands from tho centre of distribution, 

 i.e. from New Guinea, and not from Australia, which has no species 

 common to New Zealand or New Caledonia. Islands in the vicinity of 

 New Guinea contain a number of peculiar species ; but as the distance 

 from this centre diminishes, the number of peculiar species rapidly 

 decreases. Among lizards the skinks and geckos are widely distributed, 

 but snakes no less than Batrachians diminish rapidly in passing eastwards 

 from New Guinea. New Zealand, as regards its reptilian fauna, is very 

 sharply separated from the other islands of the Pacific, all its species 

 being peculiar. 



* Comptea Rendns, exxxii. (1901) pp. 1441-2. 



t Arch. Mikr. Auat., lviii. (1901) pp. 247-376 (2 pis. and 1 fig.). 



J Zool. Jahrb., xiv. (1901) pp. 380-7. 



