Ther wea SP Oak VY 
dried, in order to keep by me, are of a dark 
gray, Ihave fometimes obferved four Flies to 
proceed from one of thofe Willow rofes, but. 
they were four times lefs than thofe kinds, 
which require each a whole rofe to itfelf. Thefe 
fmaller Flies were of a refplendent jetty black 
colour, had fix legs, and fhorter horns than the | 
other kind. Their two wings were adorned 
with a black fpot, each in the middle of its ex- 
of INSECTS. 
tremity: fome of them alfo were provided with 
a fharp aculeus or weapon at the tail *. 
At ptefent Ican fay no more of thefe Flies, 
being fo much taken up with other bufinefs at 
the time*of my writing thefe obfervations, that I 
have not leifure duly to revife them. I muft 
therefore refer this tafk to another opportunity, 
if it fhould pleafe God, the difpofer of all things, 
to offer me the means of performing it. 
87 
Of certain Worms without feet, found in the Hazel-nut. 
HESE Wormsare fo common, and fo eafily 
to be had, that a defcription of them may 
feem in fome degrees {uperfluous. Their bodies are 
white, foftand hairy, their heads arered, and armed 
with two fharp teeth, with which, in autumn, 
they bore themfelves a paflage through thofe 
nuts in which they had hitherto refided; but 
which they then forfake. Thefe Worms may be 
found fometimes lying in hundreds together, at 
-the bottom of drawers and bafkets, in which 
hazel nuts have been kept. I have often formed 
arefolution of examining accurately the nature 
and difpofitions of thefe Worms, but have not 
as yet an opportunity of doing fo. Neverthelefs, 
I fee no reafon to doubt, but that they, as well 
as all other animals, derive their origin from an 
egg, thruft from abroad into the fubftance of 
the young nut, or perhaps into the bud or flower, 
out of which it is to be formed, as has been al- 
ready obferved, of many other little animals of 
this kind. 3 
There is no keeping thefe Worms in dry 
. boxes; for they will live in this confinement but 
afew weeks. Butin pretty moift fand, fome of 
them have furvived with me the rigour of a 
whole winter, and lived to the 24th of March ; 
and all that time without any food. Some of 
them, after undergoing this fevere treatment, 
were yet vigorous enough to fet about their mu- 
tations: but, by digging continually into the fand, 
in order to fatisfy my curicfity, in feeing what 
they were doing, I wounded fo many of them, 
that as yet I have not been able to difcover what 
kind of creature they finally become, 
I obferved befides, that fome of them bur- 
rowed much deeper into the fand than others; 
and I even found fome at three inches under the 
furface. I never could perceive any web about 
them, nor do I believe that they form any, as they 
always appeared lying in the fand entirely naked. 
Neverthelefs, Ido not think there is any reafon to 
doubt, but when thefe Worms efcape from the 
nuts, and leave the hazel fhrub to live in or un- 
der the ground; they, in this laft fitaation, 
change to Nymphs, and afterwards, in the en- 
fuing {pring, to a kind of Flies, which again 
depofit in the tender rndiments of young nuts, 
eggs, like thofe from which themfelves origi- 
nally were produced. It would be no difficult 
matter to afcertain, by experiment, the truth 
of this conjecture, 
Of Worms found between the two coats of the Alder-leaf. 
| FIRST OBSER VA PION. 
Q* examining fome Alder-leaves on the 2oth 
of Auguft, I.obferved the fubftance lying 
under the furface, formed by the internal coat of 
the leaf, was in many of them irregularly gnawed 
away in little angular cavities, without any paf- 
fage to the outfide of the leaf, that I could dif- 
cover; nor had the leaves, in which thefe cavities 
appeared, loft any thing of their greennefs or frefh 
hue, as the Willow-leaf jaft {poke of had done. 
The internal coat, hollowed in this manner, rofe 
confiderably above each hollow, into a kind of 
little canopy, Tab. XLIV. Fig. xvii. a, whereas, 
on the oppofite parts, the other fide of the leaf, 
which iscovered by the external coat, was only a 
little altered by a few {mall wrinkles, 54; this no 
doubt was the true caufe of the extraordinary 
roundne{s and convexity of the oppofite tumor. 
On opening one of thefe fwellings, I dif 
covered between the two coats of the leaf now 
fpoken of, a perfect web, formed exaétly. like 
that of the Moth in its Worm-fiate; and, on 
opening this web, I difcovered a Chryfalis, c, in 
point of fhape and conftruation, plainly belong- 
ing to the fecond mode of the third order of 
changes. ‘The fkins under. which this infeé 
had lived in the Worm-ftate, lay near it under 
the fame web. I could alfo difcern that it was, 
by means of this web, the Worm had reduced. 
the furface of its cavity, formed by the external 
leaf, to the appearance already defcribed. On 
each fide of the web lay the Worm’s excre- 
ments, The method ufed by this Worm, to 
form itfelf, between the two coats of a leaf, a 
cavern or neft in which it may conveniently 
perform its mutations, is certainly one of the 
moft forprifing objects that, natural hiftory offers 
to our confideration. 
As to the Worms theméfelves, I could not dif- 
cover any of them, or any of the eggs, out of 
which they muft have been hatched. In all the 
leaves I examined for this purpofe, there appeared 
nothing, only webs; fo that the feafon, for 
finding eggs or Worms was certainly elapfed, at 
the time when I looked for them. The Chry- 
* The females have all of them this weapon at their tail; the males never. The reafon is very plain, for its ufe is to bore a hole 
“ in which to lodge the eggs; therefore only the female has occafion for it. 
various {pecies of Flies. 
This author has cbferved the fame on other occafions, in 
falis, 
