53S PEOF. T. MV. BEIDaE ON THE 



easily be explained away in accordance with either theory. "With 

 a more precise and definite acquaintance with the physiology of 

 the organs in question, and a more extended knowledge of the 

 habits and mode of life of the Eishes concerned, it is possible 

 that some definite conclusions may be arrired at ; but the final 

 solution of the problem must rest with the experimental 

 physiologist. 



Whatever the significance of the inter-relationship of the air- 

 bladder and the auditory organ, there can be no question as to 

 its physiological importance. Such a connection presents varying 

 degrees of perfection and specialization in different Teleosts, and 

 its independent evolution in widely different families seems to 

 suggest the possibility that it is correlated with the requirements 

 of special or local conditions of life, and, while attaining its 

 maximum development in the dominant families of freshwater 

 Teleosts *, is nevertheless present in simpler forms m a limited 

 number of both freshwater and marine Eishes. 



X. BiBLIOGEAPHT. 



1. Beeschet. — Eecherches sur I'organe de I'oui'e des Poissons. 



Paris, 1838. 



2. Beidge, T. W., & Haddon, A. C. — " Contributions to the 



Anatomy of Pishes. II. The Air-bladder and Weberian 

 Ossicles in the Siluroid Pishes." Phil. Trans, Eoy. Soc. 

 vol. 184, 1893, B. pp. 65-333. 



3. Beidge, T. W., & Haddon, A. C— " The Air-bladder and 



Weberian Ossicles in the Siluroid Pishes." Proc. E-oy. 

 Soc. vol. lii. 1892, pp. 139-157. 



4. Cuvieb & Valenciennes. — Histoire JSTaturelle des Poissous. 



Tome xxi., 1848. 



5. Cuviee& Valenciennes. — Histoire Naturelle des Poissons. 



Tome XX., 1847. 



6. Hasse, C. — " Beobachtungen liber die Schwimmblase der 



Pische." Anatomische Studien, Bd. i. 1873, pp. 583-610. 



7. Owen, E,. — On the Anatomy*of Vertebrates, vol. i. Londun, 



18136. 



8. Paeker, T. J. — " On the Connection of the Air-bladder and 



the Auditory Organ in the Red Cod {Lotella haccJius).^'' 

 Trans. New Zealand Institute, vol. xv. 1882, p. 234. 

 (Abstract.) 



* 3. p. 153. 



