1909.] 



OLFACTORY ORGAN OF TELEOSTEAN FISHES, 



615 



chamber. The free edge of each is produced in the middle (as 

 in Elasmobranchs) to form a " Hnguiform process " and can thus 

 be conveniently divided into mesial, central, and peripheral 

 segments. 



Beyond the area covered by the rosette the lining membrane 

 of the chamber is smooth. The epithelial wall of the olfactory 

 chamber is separated by a layer of loose connective tissue from 

 an outer dense fibrous capsule continuous with the general 

 subdermal tissue of the head, the whole being to a considerable 

 extent surrounded by lymph spaces. The entire organ lies in 

 a hollow in the ethmoid (text-fig. 189) just above and behind the 

 ethmo-palatine articulation and is in no direct relation with 

 either the buccal membrane, jaws, or jaw muscles. 



Text-fig. 189. 



P.ETH.A. OL B 

 P.PMX.L. I /v. 



E.MX.L. 



Gadiis ceglefinus. 

 The relation of tlie nostrils to the deeper bones of tlie face. 



The olfactory tract passes through the skull by a foramen in 

 the lateral ethmoid below the anterior end of the frontal scute 

 and at once joins the olfactory bulb which is connected to the 

 deep surface of the rosette by short nerves. 



In the Cod {Gadus oiioi^rhua), Bib {G. hoscus), and Whiting 



