Thetis 7 OR A 
members, which are feen in the Butterfly, deli- 
neated in No. VI. As the two horns on the head, 
aa; the double curled probofcis or trunk, placed 
in the lower part of the head, between the horns, 6; 
and four wings fituated on the two fides of the 
thorax, ¢c; between which are likewife feen 
fix legs; and laftly, the abdomen divided by its 
annular fections, dd. All thefe things appear 
fo clearly and diftin@tly to the eye, in a natural 
example, that there is not the leaft room to 
doubt the truth of the fact. This is the very 
‘creature intimated in No. V. and called in that 
{tate an Aurelia, or a Chryfalis; tho’ it fcarce ex- 
pofes to our view any parts, which agree with 
the creature of the fourth Figure: yet it has no 
other than the fame limbs and parts, only they 
are difpofed in a different manner, as I fhall ex- 
plain hereafter. It will then likewife appear 
that thofe, which I reprefent feverally in this 
Tab. XXXVII. are all but one and the fame 
creature, only hidden, as it were, under different 
forms ; and this is likewife the cafe in man, if 
we confider the original egg, with its coverings, 
the navel ftring, and its feveral changes; as I 
fhall explain at large hereafter. 
To thew moft diftinaly the difference between 
the Butterfly drawn out of the {kin of the Cater- 
pillar, and reprefented in Fig. 111. and the fame 
Butterfly, when called a Chryfalis, or Aurelia, 
as delineated in No. V. It muft be obferved, that 
the real difference confifts only in this, that the 
limbs, that is the legs, wings, &c.. are ranged 
and difpofed in the Chryfalis, according to a cer- 
tain order and neceflary rule; and, on the other 
hand, that thefe parts are by art rudely unfolded, 
and turned out in the Butterfly, drawn from the 
fkin of the Caterpillar, and removed from their 
natural fituation, which they obtain firft under 
the {kin of the Caterpillar, and afterwards in the 
Chryfalis. 
“Hence the Chryfalis, No. V. is nothing elfe 
but the Butterfly exprefied in Fig. 111. the ex- 
panded parts of which are folded, and difpofed 
among one another in a different form and 
order. 
It muft be at the fame time carefully obferved, 
that thefe limbs, and other parts, are found to 
be of three diftiné: magnitudes: for, in the Ca- 
terpillar, No. IV. the limbs are ftill fmall, and 
concealed entirely under the fkin; and then 
in the Caterpillar, or Butterfly, ftripped of its 
outer fkin, Fig. 11. they are extended much 
larger ; and laftly, in the Butterfly, under No. VI. 
they are larger. Yet this obfervation muft be par- 
ticularly attended to, becaufe the three creatures, 
juft now mentioned, are one and the fame, and 
their limbs and parts alfo are the fame. But as 
to the larger or {mialler fize of them, that de- 
pends only on the blood and humours, which be- 
ing moved in the limbs, has at length extended 
them as much as poffible, In the creeping Ca- 
terpillar, it was not poffible for thefe members to 
increafe much: and inthe full-grown Caterpillar, 
they could not be produced further than the {kin 
was capable of being diftended: but under the 
form of a Chryfalis, there has been a confider- 
ably greater extenfion ; fince the external {kin is 
of Ei Ny Sahat 246. 27 
there caft off, and thefe parts have acquired an- 
other form. However, they are not yet arrived 
to their full fize; fince the laft fkin, which the 
Chryfalis muft throw off, could not be extended 
further than the folds and wrinkles, into which 
it was contracted, could give way by unfolding 
or difplaying themfelves. It happens in this 
ftate, that the creature neceffarily wants all that 
miotion, which it had before under the form of 
a Caterpillar, and muft reft for fome days, until 
the blood and humours, with which its limbs 
were filled and diftended, are diflipated {uffici- 
ently by means of an infenfible evaporation, and 
then the faculty of moving is reftored to it. 
Hence, therefore, it is certainly and clearly 
evident, that one animal is here, as it were, 
hidden or enclofed in another: nay, that the 
Caterpillar and Chryfalis are the Butterfly itfelf, 
but enclofed or covered by an hairy and cutane- 
ous coat; and {o altered by the different difpofi- 
tion of the parts, that it cannot yet be known, 
This is the fact which I propofed to demon- 
ftrate. And nothing further now remains, but 
to defcriBe the difpofition of the limbs under the 
{kin of the Caterpillar, No. 1V. for which pur- 
pofe, I muft compare thofe parts one with an- 
other, as they are conftituted in the Chryfalis, 
under No. V. for thus it will be evident, how 
the members of the Butterfly, drawn out of its 
fkin, are difpofed as well in the Caterpillar, as 
in its Chryfalis. 
As therefore the difpofition and arrangement 
of the parts in the Butterfly-Chryfalis, is found, 
in No, V. to be worthy of the greateft admira- 
tion, I fhall obferve, that thefe fame parts are 
not lefs admirably difpofed in the Butterfly, 
when drawn out of its {kin, Fig. 1v. this perfect 
animal being at all times hidden and enclofed in 
the Caterpillar, No. IV. The legs, which in the 
Butterfly, at the time it lies in the Chryfalis-ftate, 
are ftretched between the horns, and placed on 
either fide in the breaft near the trunk, are in the 
Caterpillar fomewhat curled and complicated 
under the fkin of the fix fore-feet of that crea- 
ture: for, as the impelled blood could not equally 
extend them in that part; they therefore appear 
there fomewhat <vrinkled and inflected: that 
continues until the fkins are at length caft off, 
and they are again extended as much as _pof- 
fible, in the Butterfly-Chryfalis; and whilft the 
{kin is outwardly drying, they are joined one with 
another, 
The wings, which in the Chryfalis-Butterfly, 
are evidently extended in each fide of the b-eaft 
near the horns, are placed under the fkin of the 
Caterpillar, near the under legs of the firft cla(s ; 
nay, their ends are enclofed in the fkin of the 
fame legs. This ought to be carefully obferved ; 
fince this is the only reafon why, when the Ca- 
terpillar is changed into a Chryfalis, the limbs 
are neceflarily thus, and not otherwife, difpofed ; 
for thefe legs and wings are, at the time the old 
fkin is cafting off, drawn downwards, together 
with the flkin in which they lie, and are then 
regularly difpofed on the breaft, near to and be- 
tween each other: and this is performed with 
{ach great art, and in a manner fo fingular, thit 
this 
