322 ON THE CLASSES OF THE 



the Acephala form one or two such, is by no means accu- 

 rately ascertained, though enough is known of the Mol- 

 lusca to incline us to suspect that they are no less sub- 

 jected in general to a circular disposition than the four 

 other great groups. It may at first be imagined, that each 

 group resolving itself so constantly into five others, is an 

 effect which can only be attributed to some accident which 

 may have favoured this species of developement; but there 

 aretoomany conditions to be fulfilled before we can consider 

 this supposition as in the slightest manner probable. The 

 regularity which is conspicuous in the whole distribution 

 of the animal kingdom, as above given, can proceed from 

 no other cause than design. Whether this regularity be 

 in nature, or whether it be merely part of an artificial sy- 

 stem, which I now am uselessly proposing to the scientific 

 world for their examination, may not perhaps be very 

 becoming in me to determine : but I can safely say that 

 almost all the groups here laid down have been proposed 

 by others ; so that in this respect, at least, there will be 

 some room for remonstrance, if I should be judged to 

 have wrested the animal kingdom to any theory of my 

 own. Indeed, when it is considered that there were so 

 many affinities to be reconciled with this constant use of the 

 number five, it is clearly absurd to imagine that I would 

 have hampered myself needlessly with such a rule. My 

 sole object has been to demonstrate natural affinities; and 

 in doing this I have fallen on a distribution into five groups 

 so uniformly, that where there seems to be an exception 

 to the rule, it appears to be as much the consequence of 

 our little acquaintance with the manifold productions of 

 Nature, as of any other cause whatever. No person, 

 however, can be more reluctant than I am to make any 



