has been confined to the very imperfect bounds of the last edition 

 of the Systema Nature. 



And as, like the division of labor, classical arrangement pretends 

 to nothing more than that, by clear and consecutive deduction, the 

 several distinct subjects should be brought to nominative identity, 

 passing through the direct genealogy of their several kingdoms, 

 tribes, orders, and families : whether these ends be effected through 

 natural alliances or artificial combinations, it does not appear to be 

 of much importance, supposing them to be equally comprehensive, 

 communicable, and demonstrable. 



But in pursuit of a natural arrangement, the neoteric writers of 

 the French school have constituted the organs of the animal as the 

 primary and essential base, making the shell a secondary object of 

 consideration, and absorbing Conchology into a minor branch of 

 Helminthology ; a connexion which must suppose more of tradition 

 and gratuitous admission than of demonstration, and which in our 

 present very imperfect knowledge of the Vermes, we consider to 

 be unnecessary if it were possible, and impossible if it were 

 necessary. 



We have attempted an arrangement upon principles easily 

 communicable, and strictly demonstrable, which, like the systems 

 of Botany and Zoology, are certainly artificial, but which, on a 

 comparison with the natural connexions of Lamarck and Cuvier, 

 will be found to coincide with singular " semblable coherence." 



