Thes Hal S Tb ORY of LN Sabic- Tis, 
The very moment the female has depofited her 
eggs, the male forfakes her, having performed 
the tafk, for which this laft was fo wilely de- 
figned. 
This wonderful copulation is perfomed in the 
the following manner. As foon as the male has 
leapt upon the female, he throws his forelegs 
round: her -breaft, Tab. XLVIII. Fig. 1 and 11. 
aa, and clofes them fo firmly, that I found it 
impoflible to loofen them with my naked hands 
without wounding them; fo that I found myfelf 
under a neceflity of introducing an iron fpatula, 
between the female’s breaft and the male’s legs, 
the better to feparate them. The male moft 
beautifully joins his toes between one another, in 
the fame manner as people do their fingers at pray- 
ers. His head refis on that of the female, 44, 
but in the hinder part, his body hangs a great 
deal lower than her’s, as he lies fo much more 
backwards than fhe does: this pofture has its 
ufe, which I fhall hereafier relate. The thumbs 
of the male’s forefeet prefs with their thickeft 
fides againft the breaft of the female, and the 
extreme joints of the thumbs are bent a little. 
Let the female fhake herfelf ever fo much 
at this time, the male never lets go his hold, 
even tho’ fhe fhould get out of the water, fo 
that one may carry them any where in this 
pofture; which is likewife the cafe of garden 
Snails, whem engaged in the fame bufinefs. 
Such is the male’s eagernefs to act his part, 
that he is not to be parted from his mate, even 
by pulling him forcibly from her by his hind 
legs. Thus thefe little animals fwim, creep, 
and live together for many days fucceffively, 
till the female has fhed her eggs, which, at 
length, fhe does in a manner inftantaneoufly. 
T obferved, that when they breathed, during 
this intercourfe, the external kin, which im- 
mediately covers the drum of the ear that lies 
under it, near the eyes, Tab. XLVUI. Fig. r. 
¢¢, continually heaved up, and then fell again 
againft that organ of hearing; and this alter- 
nate elevation and depreflion affords a pretty 
fpectacle, when they both breathe, and open 
and fhut their noftrils by turns. 
. It may be afked, at what time the male 
leaps upon the female? Whether it be before 
the eggs have paffed through the tubes, or after 
this, when they are already heaped up in the 
uterus? But this circumftance I omitted to 
examine. However, Icannot help delivering 
it as my opinion, that the male afcends the 
female when the eggs have been taken up by | 
the tubes, and fome of them have begun to 
adhere to the uterus. My reafon for thinking 
fo is, that otherwife the male might defeat all 
his endeavours, by compreffing and clofin g with 
his arms the mouths of the tubes. Perhaps, 
alfo, it is for this reafon, that fometimes fome 
of the eggs remain in the abdomen, after the 
others have been ejected. But a certainty, in 
thefe cafes, might be eafily obtained by dit 
fection. ; 
rift 
When, therefore, all the eggs of the female 
are got together in her uterus, the tubes are 
quite empty; and when every egg has received 
its coat of white in thefe tubes, or in the horns 
of the uterus, fhe throws them all out together 
by a fingle effort; and, while this is doing, it 
“may be obferved, that the male aéts the part 
of a midwife, and promotes the expulfion of 
the eges by working with his thumbs, and 
comprefling the female’s body harder with his 
fore legs. ‘Thus, at laft, the eggs are difcharged 
at the female’s fundament in a long ftream, d; ~ 
and the male, who has no penis, immediately 
fecundifies, fertilizes, or impregnates them, by 
an effufion of his fperm, which he likewife dif- 
charges at the anus, ¢, *. But as the eggs, 
rendered very clammy and glutinous by the 
white that invefted them, have grown together, 
had been compreffed in the uterus, they imme- 
diately, on being caft into the water, expand 
themfelyes into their former round form, ie 
Hence appears the neceffity of the hinder part 
of the male’s body hanging more backwards 
than the female’s. As foon as thefe egos have 
efcaped from the female’s body, between her’s 
and the male’s hinder legs, and have been im- 
pregnated by the male’s fperm, the two F Togs 
abandon each other. The male fwims off, 
and works his fore feet as before, though they 
had continued fo many days fucceflively, with- 
out the leaft motion, in the moft violent ftate 
of contraction. 
The eggs thus dropt, immediately fink to 
the bottom of the water, unlefs hindered by 
weeds that grow in ditches, or the like; and 
in a few days they return to the furface again, 
if not {topped in the fame manner. I opened 
a female about two hours after the had dif- 
charged her eggs in a glafs veflel, where I had 
kept her for that purpofe, and found the ovary 
perfectly contracted, as I have reprefented it in 
the fourth figure of the forty-feventh plate, 
under the letter &  Befides, there ftill re- 
mained fome eggs in the abdomen, one in the 
ovary, and one likewife in the tube. 
Upon my proceeding, after this, to examine 
the ovary, which was emptied of its eggs, I 
difcovered, in diffecting the body, three dif- 
ferent fpecies of mufcles; namely, ftraight 
ones, interfected by four lines, and oblique 
defcending and afcending mufcles, lying under 
the former. When I had laid open the abdo- 
men, I obferved a very remarkable fingularity 
in the ovary. In the firft place, I could difcern 
in it eggs of four different fizes and colours. 
Some of thefe were very {mail and white, Tab. 
XLVI. Fig. i. aa; others a little bigger, 
and yellow, 4; a third kind was a good deal 
bigger ftill, c, and of a dufky colour. There 
were likewife in this part a great many black 
little fpots, ¢, which, at firft fight, I took for 
fo many eggs ; but the microfcope proved they 
were irregular particles, or eggs beginning to 
decay. 
'_™ Ithad been fuppofed that this method of impregnation was peculiar to Fifhes; but this is one inftance of the contrary. Some- 
thing nearly analogous is the cafe with the Water-Newt, and probably future experiments will fhew it in other water animals. 
On 
