[ ] 
valves, which are opened towards the place of the 
eye; it often hides one or both of them under the 
breaft between the four legs ; thefe antennce feein 
to afford as great an amufement to the animal, as 
they do to the fpeclators. 
At the place where the head joins the body, to- 
wards the border of the hinge of the fliell, one 
may perceive a little black fpot, \vhich is the ani- 
mal’s eye. This extraordinary fituation of the organ 
of fight upon the neck feems ahoniflfing ; every 
thing that is new is fo, but the furprize arifes only 
from the narrownefs of our ideas. Many people 
would give very fpecious reafons for this polition ; 
others might fuppofe, that if the Creator had confulted 
us upon the matter, the eyes fliouldhave been placed 
in a quite contrary pofition, towards the extremity of 
the head. How childifli and weak would this be ! 
What God does, is undoubtedly mod perfedl ; and 
what he orders the bed pofiible : but what we term 
final caufes, are feldom any more than conjectures, 
though fometimes they happen unexpectedly to be 
true. Some aquatic infeCts have the eye in the fore- 
head, others at the bottom, on the fore or back part of 
the head, at the fide or under it ; nay there are 
fome, whofe head confids of the eye only. The 
plain reafon to be given of the different pofitions of 
the principal organs, is at the fame time the mod 
probable, or at lead the mod within our compafs. 
The Governor of the world is pleafed to give in- 
finite variety to his works, and only obferves the 
laws of uniformity in the generation of each didinCt 
fpecies, 
6 The 
