1909.] 



OLFACTORY ORGAN OF TELEOSTEAN FISHES. 



641 



an aspirator, althougli it can undoubtedly be compressed by the 

 retraction of the premaxilla. 



The lachrymal sac, on the other hand, is evidently most 

 effective in pi'oducing water currents in the nose, for its lower 

 border is extensively indented by the coronoid border of the 

 mandible when the mouth is closed. 



Berycid.e. 

 Beryx delphinus. 



The nostrils lie about halfway between the eye and the snouo 

 towards the dorsal line of the head, surrounded by the nasal, 

 lachrymal and frontal bones. Both are large, oval, and widely 



Text-fig. 208. 



£TH. 



O.E. 



ADO.M. 



Seryx delphinus. 



Left olfactory organ, from the side. 



PA.PT., palato-pterygoid arcade. 



S.O.E., supraorbital extension of the nasal cavity. 



open, the anterior about half the size of the posterior. The 

 bridge of skin between the two is relatively narrow and is pro- 

 duced as a transverse curtain into the cavity of the olfactory 

 chamber. 



Proc. Zool. Soc— 1909, No. XLIY. 44 



