A Short Explanation 
Thefe eyes, by imperceptible degrees, grow 
browner, and appear through the fkin, and 
at laft become entirely black. 
c Is a certain white tranfparent part, in the 
middle of the nit, which we have often feen 
beating regularly in the fame manner as the 
heart. ‘This_little part is reprefented in jig.. 
VI. by letter 4, and called by us the pan- 
creas, becaufe it moves up and down with 
the ftomach. . 
F eG. Ie 
The fhell of the egg, or the empty nit, and the firft 
Skin which the Loufe cafis. 
li 
a The border or margin of the head burft 
open, with. its little cups or uvule, and 
turned back by the Loufe’s creeping out at 
the upper extremity. 
b The other part of the empty and caft fkin of 
the nit, from which the border of the head 
' is feparated, by which means it has the ap- 
pearance of a tankard without its cover. 
Pd Gail. 
Shews the Loufe placed on its belly, and magnified 
by the microfcope. 
There appears a fhining fkin on its head, 
with fome little holes and divifions. Upon its 
breaft or back there is an elegant delineation of 
a fhield, which is as it were painted in the 
middle; and this fhining fkin is ornamented 
with little holes. To the breaft are fixed the 
legs, which are full of little fwellings or extu- 
berances, like thofe on the fhagreen fkin ; but 
they become by degrees imperceptible at the 
extremity of the legs. By the afliftance of the 
microfcope it has been difcovered, that at the 
margin of the abdomen, the fkin there appears 
alfo painted and rough, with little grains like 
fhagreen as before defcribed ; but by the help 
of the beft micrefcope, I have at laft found that 
the {kin is really formed of irregular chequered 
work, globules, and fuch like appearances. 
N. B. In fig. IV, next to be explained, will 
be pointed out by letters all the remaining parts 
of the Loufe, one after another. 
Pe rv, 
The external and internal tranfparent parts and 
limbs which are feen in the Loufe, as lying on 
its belly. 
a The Aculeus or fucker. 
65 Theantenne or little horns. cc The eyes. 
dd The fix legs. eeee The claws. 
Ff The cloven tail, in which the anus is feen. 
gg The white tranfparent veffels in the belly 
and breaft, which are properly the ramifica- 
tions of the trachea. 
123 4 &c. The feven orifices of the pulmonary 
pipes, on one fide of the body, which with 
of the: INA0B Eghks: 
feven others on the oppofite fide make to= 
gether XIV. 
hbb The large branches of the afpera arteria, 
in their firft beginning where they open by 
fpreading branches into the extremities of 
the belly, and afterwards communicate to- 
gether by an anaftomofis, or inofculation. 
Gam: 
The Loufe, hing onits back, delineated according 
to tts natural fize. 
Eee ee., Vi. 
The Loufe delineated with the afiflance of the mi- 
crofcope, tn which thofe parts which could not 
be fhewn in fig. IV, are bere reprefented, 
a A brown tranfparent part of the abdomen, 
which is obferved to be in continual motion, 
with its double tranfparent appendages, which 
are {tretched far into the breaft. This brown 
part with its appendages, is properly the 
ftomach; in the middle of them is placed 
the {pinal marrow. 
6 A white fpot in the middle of the belly, 
tranfparent, which I imagine to be the pan- 
creas. Ina live Loufe it appears to be united 
with the ftomach, and, together with it, is 
moved up and down. 
Further, in this Loufe, the articulations 
of the legs with the breaft may be plainly feen, 
alfo the bright tranfparent pulmonary pipes, 
together with the black coloured contents of 
the ftomach. At the extremity of the abdomen 
appear the double claws, like crefcents, which 
cover the vulva. 
Pol Ge Val. 
The branch of the afpera arteria of the Loufe, 
confiderably magnified, yet reprefented in its 
natural form. 
a The rings of the trachea, by which it 
ways kept open. : 
6 'The ferpentinewindings of thofe rings. 
¢ The part where thofe windings appear to be 
interrupted. 
d The part where the rings are largeft. 
e The part where the rings become {mall again, 
when the afpera arteria fhoots out into ano- 
ther branch. 
J A fimall membrane in the middle of the rings, 
which properly contains the air. 
is al~ 
FIG. Vill. 
| The feven orifices or refpiratory points of one fide, 
oy Separately delineated, 
We tng O7 Thefe figures fhew the natural 
fituation of the refpiratory points or ol 
, ¥ 
