126 REMINISCENCES OF 



embodied in a second memoir, read before the 

 Royal Society in 1850 and published in Part II. of 

 the "Philosophical Transactions" for 1851. 



These two memoirs enunciate several new 

 truths, sufficiently important, indeed, to bring Pro- 

 fessor Kolliker, the distinguished anatomist of 

 Wurtzburg, to Manchester, with the object of 

 studying the specimens from which my new con- 

 clusions were drawn, and with nearly all of 

 which he cordially agreed. In past years there had 

 been much discussion respecting the relationships 

 which the human and other mammalian teeth bore 

 to the skeletons with which they were associated. 



My investigations among the scales and teeth of 

 fishes led me to the conclusion that these dermal 

 scales and oral teeth were identical, or rather, what 

 are technically called homologous organs ; in other 

 words, that teeth belonged to the skin and not to the 

 skeleton. This novel and unexpected determination 

 was speedily accepted by Huxley. 



The absolute truth of this determination was 

 afterwards demonstrated by Mr. Charles Tomes, the 

 eminent dental surgeon. That gentleman investi- 

 gated the origin of oral teeth in the dog-fish, a close 

 ally of the shark, and the shagreened skin of which 

 is one mass of minute dermal teeth. He showed 

 that in a very young condition of these fishes a fold 

 of the shagreened skin extended round the lip and 

 entered the mouth; certain of the dermal teeth thus 

 introduced became planted upon the several oral 



