4 INTRODUCTION. 
Variation through the whole kingdom of Nature is the rule 
and not the exception. It is the prejudice exhibited by Scientists, 
against so much that is clear and distinct, that creates confusion. If 
studied as it exists, the whole group is manifestly developed, step 
by step, and we see the wisdom, power and beneficence of the 
Maker. We see the qualities implanted in these creatures to enable 
them to construct their houses with consummate skill, and to 
ornament them, either plainly, in Quaker fashion, or most elaborately 
in external sculpture. Men are constantly inventing theories to 
account for changes occurring in Natural History objects, and 
everything must bend to suit their special hypotheses. 
Only one arrangement can be correct, and we: have only to 
examine the materials and gain an extensive knowledge of the 
sections in each division to be convinced of this truth. 
The greater part of the works on Natural History are written 
in the closets of the authors, who both theorise and copy to a large 
extent ; but, unfortunately, they copy errors as well as facts. 
The study of variation has opened up a subject so vast in 
its dimensions that the mind almost shrinks from the task of 
estimating it. In every direction variation extends, in every way 
variation seems to ramify, until we gaze and wonder if there be 
any end. 
Instead of 200 Species, at least 5,000 Varieties are before 
me, and the end appears nearly as far off as ever. Taking 
a careful survey of the shells under consideration, and noting more 
particularly the common forms and the changes presented by them, 
we are enabled to form an estimate of the enormous number likely 
to be met with, if we persevere in our work of collecting varieties. 
Species are and have been made by men in their ignorance. 
Had they known the alliances, it would have been impossible for 
them to have committed such mistakes as are to be found in concho- 
logical books. Species have been and still are the ultimatum 
of scientists. It appears to me that they have an instinctive 
horror of the nameless. Lamarck described the Nassa sub- 
spinosa from shells that were subspinous, not then knowing 
that there were carinated, costated, muricated, and smooth 
