836 
ENTOMOLOGY. 
that the flighted touch will difcompofe them. The ex- 
terior part ot the chryfalis is at firft exceedingly tender, 
foft, and partly tranfparent, being covered with a vifcous 
fluid ; this (oon dries up, thickens, and forms a cruft 
round the animal, capable ot refilling external injuries; 
a cafe, which is at the fame time the fepulchre of the 
caterpillar, and the cradle ot the moth ; where, as under 
a veil, this curious transformation is carried on. The 
pupa was firft called a chryfalis, or creature made of gold, 
trout the retplendent yellow colour with which feme 
kinds are adorned. Reaumur has fhewn us whence they 
derive this rich colour; that it proceeds from two fkins, 
the upper one a beautiful brown, which lies upon or co¬ 
vers a highly polifhed and fmooth white (kin; the light 
reflected from the laft, in palling through, gives it the 
golden yellow, in the fame manner as this colour is often 
given to leather ; fo that the whole appears gilt,-although 
no gold enters into the tinfture. The .chryfalis of the 
common white butterfly furnifhes a mod beautiful objedf 
for the lucernal opake microfcope. 
_ Thofe who are defirous to difeover diftinCtly the va¬ 
rious members of the moth in the pupa, fliould examine 
it before the fore-mentioned fluid is dried up, when it 
will be found to be only the moth with the members 
glued together; thefe, by degrees, acquire fufficient force 
to break their covering, and difengage themfelves from 
the bands which confine them. While in this ftate, all 
the parts ot the moth may be traced out, though fo folded 
and laid together, that it cannot make any ui'e of them ; 
nor is it expedient that it fliould, as they are too foft and 
tender to be ufed, and pafs through this ftate merely to be 
hardened and ftrengthened. To examine the moth con¬ 
cealed under the fkin of a caterpillar, one of them fliould 
be taken at the laft change ; when the fkin begins to 
open, it fhould be drowned in the fpirit of wine, or 
brandy, and be left therein for fome days to harden ; the 
fkin of the caterpillar may then be ealily removed : the 
rudiments of the chryfalis will be firft difeovered, after 
which the tender moth appears ; and its wings, legs, an¬ 
tennas, &c. may be opened and difplayed by an accurate 
obferver. 
The time which the moth or butterfly remains in the 
pupa ftate is not always the fame, -varying in different 
fpecies, and depending alfo upon the warmth of the wea¬ 
ther, and other adventitious circumflances ; fome remain 
in that fituation for a few weeks; others do not attain 
their perfect form for eight, nine, oreleven, months ; this 
often depends on the feafon in which they affume the 
pupa form, or rather on the time of their birth. Some 
irregularities are alfo occafioned by the different tempe¬ 
rature of the air, by which they are retarded or accele¬ 
rated, fo as to be brought forward in the feafon Left fuited 
to their nature and the ends of their exiftence. 
When the moth or butterfly is fufficiently matured to 
break the bonds which furround it, and of which it feems 
to be informed by its internal fenfations, it makes a power¬ 
ful effort to efcape from its prifon, and view the world 
with new-formed eyes. A (mail degree of motion, or a 
little inflation of the body, is fufficient to enlarge the 
hole, and afford the animal room to efcape from its con¬ 
finement. When the moth firft fees the day, it is humid 
and moift ; but this humidity foon evaporates, the interior 
parts dry and harden as well as the exterior; the wings, 
which are wrinkled, being thick and frtiall, then extend 
themfelves, and the fibres which were at firft flexible, 
become hard and ftiff. The wings, though at firft fcarcely 
half the length of the body, foon acquire their full fize : 
nor is it the wings only which are thus rapidly increafed ; 
all their fpots and colours are proportionably extended, 
fo that what at firft appeared as fo many confufed points, 
become diftinCt and beautiful ornaments ; and thofe that 
are furnifiied with a tongue or trunk, curl and coil it up. 
When the wings are unfolded, the tongue rolled up, the 
parts fufticiently dried, and the different members ftrength¬ 
ened, it takes its flight. Moft of them, foon after they 
z 
have attained their perfect ftate, void an excrementitious 
fubftance ; and Reaumur thinks that they eject very little 
if any, during the reft of their lives. If the moth be now 
opened down the belly, the grofs artery, which is called 
the heart, will be vifible, and the contractions and dila¬ 
tations, by which it puflies forward the liquor it contains, 
may be eafily obferved. One of the moft remarkable cir- 
cumftances is, that the circulation of this fluid in the 
winged ftate is directly contrary to that which took place 
in the caterpillar; in this, the liquor moved from the tail 
to the head, whereas ih the winged ftate, it moves from 
the head to the tail ; fo that the fluid which anfwers the 
purpofes of blood, goes from the fuperior towards the 
inferior parts ; but in the caterpillar the order is reverfed : 
it proceeds from the inferior towards the fuperior parts. 
The induftry of thofe moths that fpin cones or follicles 
in which they inclofc themfelves for their transformation, 
is well known and admired ; fince it is from -a fpecies of 
thefe, the plialcena inori, or (ilk-worm, that we derive fo 
many benefits to the community. All caterpillars under¬ 
go fimilar changes with it, and many of the genus greatly 
exceed it in beauty : but the golden tiffue in which the 
(ilk-worm wraps itfelf, far furpaffes the filky threads’of 
all the other fpecies : they may indeed come forth with 
a variety of colours, and wings bedecked with gold and 
fcarlet; yet they are but the beings of a fummer’s day ; 
both their life and beauty quickly vanilh, and leave no 
remembrance of them ; but the (ilk-worm leaves behind 
it fuch beneficial monuments^ as at once record the vvif- 
dom of its Creator, and his bounty to man. The fubftance 
of which the filk is formed, is a fine yellow tranfparent 
gum, contained in two refervoirs that wind about tite in- 
teftinps, and which, when they are unfolded, are about ten 
inches long; they terminate in two exceeding fmall ori¬ 
fices near the mouth, through which the (ilk is drawn, 
or fpun to the degree of finenefs which its occafions 
may require. 
When the filk-worm, or caterpillar of the phalsena 
mori, is about to enter its pupa ftate, it fets to work, firft 
fpinning (ome random threads, which ferve to fupport 
the future fuperftruCture ; upon thefe it forms an oval of 
a loofe texture, confiding of what is called the flofs-filk; 
within this it forms a more confident ball of (ilk, remain¬ 
ing during the whole bufinefs within the circumference of 
the fpheroid that it is forming, reding on its hinder parts, 
and with its mouth and fore legs directing and fecuring 
the threads. Thefe threads, when meafured, have been 
found to be about three hundred yards long, and fo fine, 
that eight or ten are generally rolled off into one by the 
manufacturers. The (ilk-worm ufually employs about 
three days in finiftiing this cone ; the infide is generally 
fmeared with a kind of gum, that is deligned to keep out 
the rain : within this cone it alfumes the pupa form, and 
remains therein from fifteen to thirty days, according to 
the warmth of the climate. When the moth is fufticiently 
matured, it moiftens the end of this cone, and by frequent 
motions of the head loofens the texture of the filk, fo as 
to form a hole without breaking it, and through which it 
efcapes. For more on the natural hiftory of the moth, 
and the manufacture of filk, fee the articles Phal^ena, 
and Silk. 
The coleoptera genus, or beetle, is an infeCt alfo dif- 
engaged from the pupa form, before it can attain its wing¬ 
ed ftate. The pupa is a transformation in like manner 
from the worm or larva, and this derived its exiftence 
from the egg ; fo that here, as in the foregoing inftances, 
one infeCt is exhibited in four different forms, before it 
acquires its perfedt organization, or mature ftate of life. 
The worm or grub of the beetle, like other infeCts in the 
larva ftate, in order to undergo its transformation, dif- 
charges all its excrement, and forms a convenient hole in 
the earth ; where it cafts not oft’ merely the external co¬ 
vering, but the throat, a part of the ftomach, and the in¬ 
ward furface of the great canal, change at the fame time; 
their (kin. After the transformation, the head and teeth 
are 
