it 
me 
8 The B-O°O'R “of (N A TU RBS or, 
The reafon why the limbs in the Chryfalis 
unite, and are, as it were, glued and faftened 
together, is, becaufe the ikin, invefting the 
Chry/alis in that part where the union or junc- 
tion is made, is confiderably thinner than where 
it is expofed to the air. And therefore, on 
account of this inequality of the fkin, it was 
abfolutely neceffary to preferve all the mem- 
bers from the drying air, and to defend them 
from injuries by their mutual compactnefs. 
Thefe things are circumftanced in the parts 
_of the Nymphs ina contrary manner ; for their 
{kin is found to be equally thick in all the parts, 
fo that it would be {uperfluous to unite them 
together. But, even in Nymphs, fome parts 
fometimes occur, which are covered with an 
equal fkin. This holds chiefly when fome 
parts reft upon or are fupported by others ; 
and it is obferved principally about the cafes 
of the wings, which have a much thinner 
fkin, where they receive the wings, than where’ 
they are turned to the air: therefore, in this 
refpect, they entirely agree with the Chry- 
fallides. 
It certainly deferves great notice, how deli- 
cate and thin the integuments of thofe parts 
are, where they are found to lie on each other: 
and hence even the continued fkin, which co- 
vers or inclofes thefe parts, has its external part 
thick, and is ftrong-and hard; but in the in- 
ternal part it is thin, tender, foft, and formed 
like a fpider’s web. This {kin fometimes alfo 
is fo fine, that the rays of the fun exhibit 
therein various colours to the eye, efpecially 
where it is in any degree folded: as is obferved 
in very thin and fine blown glafs, and in the 
{lender filaments of a fpider’s web. 
This being well confidered, it is eafy to un- 
derftand. why many Butterflies are produced 
deformed; that is, when their limbs, under 
the period of the transformation, are not well 
united together, as frequently happens. In- 
deed I have, more than once, feen that they 
have dried and perifhed, by reafon of this de- 
fet of a proper union. The fame effect 
may be performed by art, and a certain opera- 
tion: I mean, we may thus produce Butterflies 
that are deformed. Ican alfo very eafily dif- 
unite all the limbs of the Chryfallides; for, 
naturally, thefe parts in the Chryfallides will 
then never feparate themfelves further, not even 
at the time they are ftripped of their fkin: for 
the fkins to be cut off from thence, have only 
three or four cracks or openings, fince the 
thinner fides of thefe invefting parts are then 
very eafily broken further, with the leaft mo- 
tion; fo that there will be no need to move 
the re{pective limbs out of their places. 
As thofe who fearch into the fecrets of na- 
ture have not obferved this, I am therefore in- 
clined to think they have imagined, in confe- 
quence of this overfight, that the continued 
{kin of the Aurelia confifted of a texture of the 
parts united one with another. They have 
therefore fancied, that the infe@ lies in that 
uniform and undivided fkin, in the fame man- 
ner as the chicken lies in its undivided fhell. 
4 
But this is contrary to all truth; for every part 
of the Chryfalis, as well as the limbs of the 
Nymph, is invefted with its refpective integu- 
ment. And this is the more inconteftably 
certain, becaufe thefe limbs, together with the 
{kin wherewith they are furrounded, are found 
entirely perfect in the Worms and Caterpillars, 
and may be even there feparated or difengaged ; 
fo that one of thefe infects is, in reality, al- 
ways in another: as I thall hereafter defcribe, 
and abfolutely prove. 
Another remarkable thing in thefe Aurelia, 
whereof we are fpeaking, is, that even the 
hairs of the Caterpillar caft a fkin, and are 
afterwards feen in the Chryfalis. And hence 
arifes another invincible argument, moft clearly 
demonitrating, that the Aurelia is not a crea- 
ture newly transformed, but is really the former 
creature, which has caft its fkin. ‘The whole 
change, or rather accretion of the parts and 
limbs, confifts indeed only in this, that the in- 
vefting membranes or fkins, which are fo many 
veils that obftruct the fight, are removed by. 
degrees, and thrown off; fo that the limbs, 
which, from the firft, lay hidden in the infide, 
are, in the end, feen on the outfide. In all 
thefe changes, nothing is more wonderful: than 
the motion by which alone they are feverally 
produced, and perfected by means too difficult 
to be inveftigated. The deeper we here look 
into nature, the more we are obliged to con- 
fefs our blindnefs, and ourignorance. Indeed, 
there is nothing more true, than that all thefe 
things, which I advance and publifh, are no 
more than the naked fhadows of the inexpli- 
cable myfteries of the Great Creator: the in- 
ternal nature, and true difpofition, of thefe 
meanders are above the reach of our limited 
underftandings. 
I fhould never conclude, if I attempted to 
profecute minutely all the wonderful things 
that occur in thefe Chryfallides: and, indeed, 
I fhould weary out the reader’s patience by a 
prolix recital of them; fince he muft firft have 
fome knowledge of the hiftory of thefe infects, 
who would properly underftand what is deli-. 
vered. I fhall add but one thing more con- 
cerning the eggs of thefe infects: this is, that 
as the rudiments of thefe eges may be perfectly 
‘feen in the Caterpillar, there arifes from thence 
a {till more powerful argument to prove, that 
there is no real metamorphofis or change, or 
real transformation of parts in the creature ; 
but only a fimple growth, or accretion, as in 
all other animals; only, that it is more confi- 
derable, and more admirable, than in the cther 
creatures. I fhall alfo add, that the egg itfelf 
is, in reality, no other than a little infect, the 
ftrength of which, by degrees, increafes in its 
{kin or coat; until it has at laft acquired fufh-. 
cient ftrength to break through this fkin or 
thell, and caft off its firft integument. It is 
therefore, from what has been faid, clearer 
than the meridian fun, of what infinite ufe fuch 
experiments are to us; as thofe I have pro- 
pofed, by way of f{pecimen, at the end of the 
third chapter. 
In 
