414 Dr. Banci'oft o?/ Jamnican Fishes^ 5i"c. 



better epithet than the latter, when its pecuHar structure shall have been 

 explained. Neither does the great Cuvier appear to have studied it 

 (probably from the want of a good specimen) as is evident from the 

 doubt he entertains as to its modus operandi; " le poisson se fixe aux 

 " differents corps, soit en faisant le vide entreles lames transversales, soit 

 " en accrochant les Opines de leur bords," Bosc is the only one who 

 has expressed a just notion on this subject ; " je reste persuade quo c'est 

 " en faisant le vide que I'Echeneis se fixe," ( Deter vi lie's Diet. d'Hist. 

 Nat. t. 10, p. 46.) but he has left us nearly as much in the dark as to the 

 anatomy of the part as his predecessors. Yet the whole of its conform- 

 ation is most curious. After dissecting such a portion of it as exhibited 

 its structure, I made sketches of the various bony and cartilaginous pieces 

 and of the several sets of muscles that act between them, and drew up 

 some account of its structure. But having afterwards succeeded in 

 getting a second specimen of the fish, I have determined to send it to 

 Mr. Bennett's (and, if necessary, to Mr. Yarrell's) charge, and to request 

 them to undertake a labour for which they are far better qualified : and 

 although I have since obtained a third specimen (which, with the first, is 

 sent in the breaker) yet I have put into the cask with these a spare disk, 

 which I partly dissected, that it might not be necessary to mutilate either 

 of those specimens by removing its disk for the purpose of anatomical 

 examination. The organ will be found nearly as complicated as the 

 spine and the ribs in vertebrated animals, and there is some similarity in 

 the play of the parts on each other so far as relates to the dorsal surface ; 

 yet the whole mechanism is singularly different, (one single transverse 

 piece for instance supplying the place of one pair of ribs and of the body 

 of the vertebra belonging to it,) and at the same time beautifully simple 

 and efficient. The outer border of the disk would of itself suffice for 

 mere adhesion to the surface on which it is applied, when a perpendicu- 

 lar force is exerted to pull it off, as in the case of the wet leather suckers 

 that bovs play with : but it offers no resistance, as I have found on trial 

 repeatedly, to a force parallel to the surface, which causes the disk to 

 slide over it in all directions. The mechanism of the lamince, however, 

 within the disk effectually supplies that deficiency. In their state of 



