2 CONCHOLOGIST S COMPANION, 
to its nature; the other is its shell, or habitation, 
which is generally hard, stony, or calcareous, partially, 
or entirely covering the inhabitant, which is attached 
to it by means of ligaments or muscles; and how- 
ever small or unimportant some of the species may 
appear, we shall certainly discover that they are as 
exquisitely contrived, and as carefully wrought for 
the place and station which they are designed to fill, 
as the higher orders of creation. Nay, further, if 
we consider, the prodigious number of individuals, 
the shape and construction of their little bodies, their 
motions, instincts, and to say no more, the incom- 
parable beauty and lustre of the colours with which 
their coatings are shaded and adorned, where shall 
we discover more striking demonstration of an 
Almighty Creator, than in this minute, and till lately, 
neglected branch of natural history ? 
Some species inhabit the sea, others fresh water, 
others again the land; their instincts in general appear 
superior to those of their relatives, the undefended 
Mollusca; and with regard to every other class of 
organized beings, there subsists, besides several points 
of resemblance, a general relation of a very peculiar 
kind. This is the relation of inversion, the law of 
contrariety. For as in other animals the bones, to 
which the muscles are attached, lie within the body ; 
in shell-fish they are placed externally. The testa- 
