XvL A Short Explanation 
FIG. XV, 
A male Ephemerus, which has caft both its feins, 
changed into a flying infect ; whofe legs, which 
an the worm-ftate were fhort, are now as long 
again as they were, but the tails which were 
_ before twice that length, are now become three 
times as long. 
TAB. XIV. 
Ee Geel 
A diffection of the Worm of the Ephemerus. 
aa The pulmonary tubes, or two air trunks, 
running along each fide of the body. 
&6 The tubes reaching to the brain and nerves. 
ddddd The pulmonary tubes tending to the 
mufcles of the abdomen, from one fide; 
but from the other fide are feen, at the fame 
letters, the naked mufcles of the abdomen, 
with their tubes, alfo the oblique, afcending 
and ftraight mufcles, hidden partly under 
the former. 
eee The air pipes, or tubes, running to the 
fpinal marrow. 
SSF FFF The air pipes diftributed through the 
fmall guts, or feminal veffels of the male. 
One of them reprefented in its natural fitua- 
tion, and another of them removed out of 
the body, and reprefented magnified more 
than the other. 
egggg The air pipes diftributed to the gills. 
Only two of the gills are here reprefented, 
the other ten being cut off, to give an op- 
- portunity of feeing the ten rowing fins under- 
neath them. See let. rrrr. 
hb The air pipes running to the loweft parts of 
the inteftines, and alfo to the fpermatic vef- 
fels placed near them. 7. 
24% The air pipes which fupply, refrefh, and 
nourith the fat, membranes, and fkin with 
air. 
kk The air pipes. 
p Three exraordinary air pipes difpatched 
beyond the body, towards the gills, cut off. 
q ‘The middle of the three firft pipes, being 
black, but about the middle fhining with 
white, in fuch a manner, that the black line 
of the gills appears as if marked with a white 
point oppofite. 
ryrrr The five rowing fins ftretched out from 
each fide of the body, with ftrong briftly 
hairs, of an obf{cure yellow gold colour, 
ss A feathery little part fituated underneath the 
firft pair of gills. 
yyyy The fpinal marrow, confifting of eleven 
knots or {wellings, from which fpring the 
nerves that are diftributed through the whole 
body. See Fig. VI. Tab, XV. 
zz The parts to which the {pinal marrow is 
faftened, by the means of {trong ligaments. 
* * The optic nerves, derived from the brain, 
or origin of the fpinal marrow, where it 
forms the firft knot or {welling. 
of the TABLES. 
a The mufcles of the breaft, employed in 
moving the legs. 
&@ The mufcles of the breaft, employed in 
moving: :he wings, cut off. 
vv ‘Two little parts, which I take for the {per- 
matic vefiels of the male. “ 
d The ftraight gut cut off, inTab.XV Fig. V. 
that it may be the more perfectly feen. _ 
ees The extremely artificial folding of the 
wing, whilft it yet lies in its cafe or fheath, 
kk. being very eafy to be unfolded. See 
Fig. IX. X. XI. Tab. XII. 
Bol. G.I. 
All the parts juft now reprefented in their natu- 
ral fize. 
TA be a 
Fil G) Yh, 
JJ Some branches of the air pipes which run 
to the ovary of the Ephemerus. 
mmmm ‘Vhe fame air-pipes running into and 
over the membrane invefting the ovary. 
e¢ The muicles employed in moving the fix 
gills and five rowing fins, placed on each fide 
of the body. 
ff The ftomach and inteftines, which are vi- 
fible through the membranes of the ovary.: 
See Fig. V. of this Table. 
zz The mufcles of the ftraight gut employed 
in voiding the feces. 
ie ie Ca ou 
The little eggs of the Ephemerus, as they appear 
to the naked eye. - 
BoGe. lie 
The double ovary of the Ephemerus, conffiing of 
innumerable little eggs. 
Be FoG dle 
0000 Some air pipes leading to the heart of 
the Ephemerus, partly cut off. 3 
tt Part of the heart, like an oblong tube, 
which is fomewhat fwollen on each fide. 
vuvuwv Some air pipes cut off, leading towards 
the heart, and then to other parts. 
xxx The parts in which the tube of the 
heart {wells up a little. . 
FFG) (Vv 
a Part of the oefophagus or gullet, cut off near 
the ftomach 
& The pylorus of the ftomach 
¢ The ftomach itfelf, with certain air pipes, 
which creep all over it. 
dd The fmall gut continued from the ftomach. 
e The thick gut or colon, diftinguifhing itfelf 
by fome little oblong tran{parent channels or 
furrows. 
Sf The 
ne Oe ea EE nS ee 
