The Ele WP OR WY . of AoNuS Bc oT. 
the thorax,’the skin came off from thofe of 
the future Beetle in the form of a {tiff theath, 
jaft asa boot comes off a man’s leg. It is alfo 
very remarkable, that the extremities of the 
pulmonary tubes were inferted into this external 
skin of the infect. But I fhall hereafter fpeak 
of this matter more at large. The inteftines 
which lay in the abdomen were formed in quite 
a different manner from thofe of the Worm, 
of which I have before given a figure, and in 
particular they had more finus’s. ‘Uhe ftomach 
itfelf ended in a kind of very {mall gut, and 
indeed all thefe alterations feemed requifite to 
prepare the parts to the great change in the 
body itfelf, which was grown at this time con- 
fiderably fhorter than before. But as the fto- 
mach was greatly abridged, and therefore its 
mufcular parts had without doubt fuffered con- 
- fiderable changes, both that and the inteftines 
were now foftened into a kind of flimy humour 
to facilitate fo furprifing a change. ‘The pul- 
monary veffels retained their former fituation 
and figure. The whole abdomen was filled 
with a kind of calcarious fubftance refembling 
ftarch, and of fo bright a white as to dazzle 
the eyes of all who faw it. Ona nearer exa- 
mination of this fubftance, I found it to be no- 
thing more than a collection of thofe little bags 
in which the fat is depofited, and which little 
by little lofe their form and office, and are at 
laft fo entirely wafted away, together with their 
contents, that not the leaft veftige of either is 
to be found in the fucceeding Beetle. About 
this time fome fpots are obfervable in this moft 
extraordinary fubftance, of a brighter white 
than the reft of it, and many of the pulmonary 
tubes feem to take their direction towards thefe 
particular parts. This induces me to think they 
may be the rudiments of the pneumatic blad- 
ders with which the Beetle is furnifhed in a 
wyatt abundance, unlefs we are rather to confider 
fuch pneumatic bladders as confifting of the 
pulmonary tubes dilated occafionally to anfwer 
that purpofe. For my own part I cannot take 
upon me to decide this point. I obferved the 
fame things in the Nymphs of Bees, after I had 
finifhed the hiftory of thofe infects: but be 
this as it will, thefe {pots are fo brittle and 
tender in the Nymph that they are deftroyed 
by the flighteft touch: by their dazzling white- 
nefs alfo they hinder, us from diftinguifhing 
properly the adjacent parts: for this reafon, to 
proceed well in our examination, we muft be 
conftantly wafhing with fair water the inteftines 
of the infect. Were it not for this obftacle, 
we might doubtlefs here diftinguifh many more 
things worth of notice. In the thorax, fome parts 
were a little more folid. The mufcular fibres 
of the legs and wings were fomewhat more 
firm or tough than the white of an ege juft 
beginning to harden. All the other parts were 
as {oft and tender as poflible. On feparating 
the external skin of the body from the internal, 
the fpace between them was found to contain a 
great quantity of moifture, but in many places 
this feparation was abfolutely impoffible, 
145 
As the feveral parts in the Nymph grow by 
degrees ftronger and ftronger, the infect may be 
feen to make a proportionable ufe of them, 
We fee the legs move within the skin that 
covers them, and even the claws that terminate 
the legs begin to brandifh themfelves up and 
down. The fame is vifible, and in the fame 
manner, in the Aureliz of Silkworms during the 
laft days before their tran{mutation: if during 
this period you ftrip the legs of their external 
skin, you will find very little moifture under 
it, Even the horny or bony fubftance which 
conftitutes the joints of the legs appears hard, 
perfectly formed, and covered with hair. 
I cannot fay how long the fcene of this in- 
fect’s mutation continues, having forgot to take 
notice of it, though at the fame time I was 
witnefs to the change of above fifty of thefe 
Nymphs into Beetles. Sometimes thefe infects 
remain in a Nymph fate during the whole 
winter, efpecially when the Worms throw off 
their skins towards autumn, and a fudden cold 
fucceeding checks their further operations. 
Hence it happens that they remain without 
food for fome months, nor could they take it 
to any purpofe, their parts being too foft and 
tender to allow them to make ufe of it. 
When the proper feafon of the Nymph’s 
final change approaches, all its mufcular parts 
are obferved to grow ftronger and ftronger, to 
be the better able to fhake off their laft inte- 
guments, and this is performed in the fame 
manner exactly as in the already defcribed 
change of the Worm toa Nymph ; fo that in 
this laft fkin, which is very delicate, the traces 
of the pulmonary tubes that have been pulled 
off and turned out become again vifible; nor 
is their number limited to eighteen, there ap- 
pear abfolutely twenty of them, as has been al- 
ready fufficiently obferved. ; 
It is now proper to fee how all the parts of the 
infect, but efpecially the wings and their cafes, 
are at this time {welled and extended by a flow 
of air, blood and humours, driven into them 
through the arteries and pulmonary tubes. 
About this time the wings are as foft and flexi- 
ble as a piece of wet paper, fo that blood iffues 
from them at the leaft wound. But when they 
have acquired their due hardnefs, which in the 
fheath or cafes is very confiderable, the veffels 
that before yielded blood fo freely, are fo firmly 
clofed, that neither they nor the wings can by 
any cutting or tearing be brought to yield the 
leaft fluid. This induces me to advance as a 
thing not to be doubted, that whereas thefe 
wings and their cafes are fo full of veffels and 
pulmonary tubes, they ought to be confidered 
as confifting entirely of fuch veffels and tubes. 
It is alfo probable, for the fame reafon, that the 
membranes and skin of the other creatures are 
no more than a complication of veffels, as 
nerves, arteries, veins, lymphatic duéts and the 
like, for fo long as the embryo’s of the human 
{pecies and of quadrupedes remain in the womb, 
their skin appears compofed of nothing elfe. The 
{ame may be faid even of the bones themfelves ; 
Pp 3 and 
