46 SENSE or SMELL IN FISHES. 



palate, *ongne, and branchiostegous rays are coTcred with 

 bony points, or laminap of different forms, which prcTcnt 

 the intimate contact of substances taken into the mouth. It 

 is true in the muscles of the hyoides and of the branchios- 

 tegous rays, placed at the lower part of the mouth, we find 

 all the ramifications of the nerves of the fifth pair, as well as 

 those of the indeterminate nerve, which evidently has the 

 ''"he great hy- place of the glossopharyngean. Yet neither I nor Mr. 

 ^*zmtinc in '^^^ Cuvier conld ever meet with the great hypoglossal nerve 

 them. ill fishes, notwithstanding our most attentive sear(5hes, when 



I enjoyed the advantage of editing his lectures on compara- 

 tive anatomy. Besides, as .this fact was of great importance 

 to tht subject of the present paper, I think it proper to 

 add, tliat I have again satisfied myself of it by fresh ana- 

 tomical researches. 

 The sensation It is easy to imagine, that the water, by its continual en- 

 d^ ^A^ "j^outh France into the mouth, and the compression it there under- 

 goes, as often as the fish exerts on it the action of degluti- 

 tion necessary to force it through the gills, must exert a 

 friction so often repeated, as to deaden all the sensibility of 

 these parts. 

 ancl the orgnn Now since the integuments of the inside of the month are 

 oftastccannot coriaceous, destitute of salivary glands, and frequently- 

 roughened with teeth' or horny points ; the tongue adherent, 

 bony, and immovable ; the great hypoglossal nerve want- 

 ing; and water continually exerting a friction on it: it is 

 very probable, that the organ of taste cannot exist there. 

 This was the first point I proposed to examine. 

 Probably it is As the organ of taste appears not to reside in the mouths 



in some other f fishes, and this sense is indispensable to animals, we must 

 part. ' 



meet with it elsewhere: and since tastes in general bear a 



considerable analogy to smells, let us inquire whether the 

 sense of smell be not to a certain degree converted into that 

 of taste. But, before we enter on this investigation, let 

 us examine the nature of these two sensations. 

 Nature of Natural philosophers, chemists, and subsequently phy- 



smells, siologists, have generally attached to the idea of smell, that 



of the sensible existence of corporeal atoms of extreme mi- 

 nuteness. Though art has not yet been able to imitate au 

 instrument so perfect as that met with at the entrance of the 



respiratory 



