. £ +39 ] 
This fpecimen is in every circumftance analogous 
to all the other animals, which annually caft their 
integuments ; and, in its prefent foft ftate, refembles 
that of a hen’s egg before the teftaceous matter is fe- 
creted by the glands of the membrane ; being foft 
and flexible : for this matter of all cruftaceous ani- 
mals, as well as of the eggs of fowls, is always fuc- 
ceflive to the intire formation of the membrane under 
it ; nor are the glands capable of admitting the mi- 
nima of the teftaceous matter, till they have grown 
into a ftate proper for that purpofe. 
Hence it may be concluded, that the crab, lobfler, 
or other fuch animal, which has this property, are, 
at firft, furnifhed with this membrane intire, and 
fufficient to be a defence for the creature, againft the 
violence of the agitated waves, and the rolling' of 
fand, gravel, or other bodies, that might prove ob- 
noxious to it, even before it can grow hard. This feems 
to be the method ordain’d by the Creator for the 
the prefervation of every animal, however differing 
in other little circumftances. The fnake, adder, li- 
zard, or any other kinds, which we fee endow’d 
with this property, have the new fldn intire under 
the fhrivell’d, falling, old one j and it is, no doubt, 
the cafe with crabs, lobfters, and other cruftaceous 
animals. 
In order to throw a little more light upon this 
matter, it may not be difagreeable to obferve the 
manner of the induration of the furfaces of the fhells 
of eggs. 
It has been fuppofed, that thefe confift of a mucus 
indurated upon the furface of the membrane : but 
this is not the cafe. The particles of the fheily 
matter 
