Phe: EL. WSU TO AR YY .tot- 3 WN She Co y'S. 
the little creatures, it ferves to confine the moi- 
fture. When this moifture is confumed, the 
downy integuments, which furrounded it out- 
wardly, become curled g into each other like 
preffed flocks of cotton ; and therefore feveral 
fuch downy clufters are found gathered toge- 
ther in the warts. ay 
The bags juft now mentioned, containing a 
fluid, are all furnifhed with a petioli, or. foot- 
ftalk, by means of which they adhere to the 
inner furface of the tubercle: but whether that 
fluid be the real aliment with which the Worms 
are nourifhed, according to my opinion, or whe- 
ther they are there fed with fome other matter, 
hasnot hitherto appeared to us from experience. 
But this is certain, that thefe Worms have nei- 
ther a trunk, nor any teeth. Nature hath gi- 
ven them only an acute and delicate converging 
beak, not unlike that of the Cicada, which fucks 
the dew: by this beak they can penetrate eafily 
énough thro’ the’downy coat of their bags, 
and fuck the moifture before defcribed. But 
whether thefe creatures do really nourifh them- 
felves in this manner, or not, I cannot yet af- 
firm, tho’ it is very probable. ce 
We poured a fmall drop of water into the 
cavity of thefe warts; and it was immediately 
covered round with that farinaceous down, and 
was deprived of its fluidity to fuch a degree, 
that when it was afterwards fhaken on dry pa- 
per, it did not wet it, but flipt and rolled over 
it, and did not ftick to it: this was a very 
agreeable fight. , | 
There is not fuch a great quantity of that 
down about the largeft, as about the fmalleft 
Worms. On thefe indeed there grew four buds 
or rudiments of coverings of legs, on each fide 
near the fhoulder-blades. I have reprefented 
them 4 on each fide of the thorax, above the 
hinder legs. The principal cafes, or firft buds 
of the limbs are, in reality, a kind of covers, in 
which the wings lie folded up. | Therefore, 
thefe creatures may then be properly called 
Nymphs belonging to our fecond order of natu- 
tural tranfmutations ; for in that order, the infects 
do not at all lofe their motion during the time 
whilft they are changing into Nymphs; but on 
the contrary, walk, ftand, eat, and move about, 
until they change their skin; and having at 
- length caft their exuvie, they affume, as it were, 
another itracture, and acquire only wings. ‘This 
miuft be well obferved. I would likewife have 
it remembered, that I have ranked thefe Nymphs 
* ‘The modern term for all Worms bred from the eggs of winged infe€ts in tubercles, 
Reaumer is the author who eftablifhed this. Some of them burrow deeper, others very flightly ; 
brane. ‘The manner of their getting through it, when their parent infeéts have lodged them 
Flies, with four wings. 
97 
in the fecond order, becaufe they perform theit _ 
& . : 
change in fo obfcure a manner, in the warts of 
the leaves. 
Thefe Nymphs, which are to change, caft a 
very fine skin or integument, which is left in thé 
cavity of the wart *, When this is caft, they 
acquire, Fig. xxv.the form of delicate {mall 
Thefe Flies are of a 
blackith colour, except the membranaceous wings, 
which have brown nerves, and elfewhere ap- 
proach fomewhat to red. The limbs, and other 
parts, that is, the head, thorax, abdomen, an- 
tenn, eyes, legs, and the reft, may be now feen 
much more diftinétly in the infe@, now per- 
_fectly mature, than when it appeared in the 
form of a fix-footed Worm. 
The horns appear to be divided into fix joints, 
and are very beaatiful,; they are compofed, as it 
were, of grape-ftones, or are like a {mall piece 
of cinnamon, incruftated or rough-caft with fa- 
gar. ‘The eyes are confiderably large, and reti- 
culated ; they appear very diftin@ly when the 
creature lies on its back. The beak is clofely ap- 
plied to the lower part of the thorax, and is there 
feen extended downwards between the firft pair 
of legs, juft in the fame manner as the Cicada. 
The wings, befides their nerves, and the veflels, 
wherewith they are elegantly diftinguifhed, ex- 
hibit two oblong black fpots, with which they 
are ornamented, . 
This creature flies very flow ; indeed it does 
not move with fo much {wiftnefs as the fmall 
Worm, out of which it is produced, I have 
not yet difcovered, by diflection, the difference 
between the male and female; nor have I ever feen 
the eggs of this Fly. -I am inclined, however, 
to think, that they are lodged by the parent, on 
the inner coat of the Poplar-leaf: and that the wart 
or tubercle here defcribed, is afterwards formed 
there by nature, in order to hatch and nourifh 
them, and to keep them in fafety. But howall 
thefe things are performed, we can yet only con- 
jeCture: fince they muft be known, not by rea- 
foning, but from folid experiments, I ‘hall 
here therefore furl my fails, and in amazement, 
celebrate the great Creator, who hath hidden fo 
many, and fuch inexhauftible natural and im- 
portant miracles, full of true knowledge and 
erudition, in hiscreatures; fo that the air, the wa- 
ter, and the earth; the plants alfo, that vegetate 
therein, abound with them ; and all vegetables 
and animals, however {mall, proclairh the glory 
of the Supreme Being. : 
or parts of vegetables, is Afcarides, 
all get under cover of the upper meni-' 
on the furface, is various; the Cater= 
pillar kind eat their way; the Worms of Beetles get in by breaking the furface with blows of their head. 
Bb 
Of 
