I C II T H 
“?ty to rid themfelvcs of this burthen throws them off 
their guard : they leave their lecure and deep hiding- 
places, and run as it were into the mouth of their greateft 
enemy, man, by coming towards the fiiores and into the 
(hallows in feareh of thole fituatiotis where they may un- 
burthen themfelves in the molt convenient manner, or 
■where they may meet with thofe fubftances againft which 
to rub their bellies when their internal efforts are not fuf- 
ticient to ejedl the ova, or the feminal liquor which is to 
fecundate it. 
It is faid that feveral females, and the faltnon in parti¬ 
cular, are inltinCtively led to depolit their eggs in a 
kind of nefts, or places little expofed to danger. Certain 
it is, that they rub their bellies in different directions 
againft the bottom of the water, moving away f'oft and 
greafy fubftances,and leaving only gravel, and ftones.well 
cleanfed by thefe motions, and that therein they depofit 
their fpawn as in a neft. But in all probability it is ra¬ 
ther from the relief they find in rubbing againft the gra¬ 
vel, than any intention of preferving their eggs, that they 
are led to this mode of proceeding ; for the greater part 
of the females abandon their eggs the moment they are 
free from them. Being now unconftrained in their mo¬ 
tions, they return to their favorite haunts to recover them- 
lelves, and to repair their ftrength. Some females are lb 
far exhnufted at this time for want of food, that they will 
immediately devour a part of the fpawn they have juft 
emitted, while it floats on the water ; this has given rife 
to another popular error, as if fome Allies were fo careful 
of their eggs as to hatch them in their gullet. Others de¬ 
vour with avidity the feminal liquor of the males, which 
lias occafioned another erroneous idea, into which fome 
eminent naturalifts have fallen, that females might be fe¬ 
cundated by the mouth. 
When the females have excluded and abandoned their 
eggs, the males arrive prefently after, attracted by the 
fmell, which reaches them at a great diftance. The}' are 
not brought thither by affeCtion for the females, who are 
already abfent; but drawn by in It in ft towards the eggs 
which they are to fecundate. Sometimes indeed they feed 
upon them, inftead of giving them life ; but molt fre- 
•quently their inftinCt leads them to ejeCt their feminal li¬ 
quor over them. But the odour of thefe ova fo ftrongly 
aft'eCts their organs of fmell, which we have before ob- 
ferved to be very exquifite, that they are led to follow the 
females while the fpawn is yet within their bodies. Then 
they are feen mingled with the females before fpawning ; 
and, prefling their bellies in the fame manner againft 
ftones and gravel, they aflift each other in the work of 
generation, though fexual attachment has no fliare in their 
inftinCl. 
Nor does the agitation of the waves prevent the fecun¬ 
dation of the eggs lb often as has been fuppofed ; lor a 
fniall drop of the whitilh liquor is fufficient to impart the 
principle of animation to a "great number of eggs; and 
feveral males are feen occupied in the fame manner near 
the fame fpot ; farther, Bloch lays, that the number of 
males is double that of the females. 
Several eminent naturalifts, and particularly Rondele- 
tius, have fallen into an error in fuppoling that water 
alone was capable of generating fifties, becaui'e they have 
been found in ponds and ditches where no filh had been 
thrown, nor any fpawn, and which had no communication 
•with lea, lake, or river. It is eafy to liippofe, that in 
fucli cafes, which are not very frequent, the fecundated 
ova of fillies may have accidentally ltuck to the feet or 
belly of certain birds who are known to feed thereon, 
and fo be dropped in thofe places. And this leads us to 
repeat the remarks of a very accurate obferver, J. L. Ja¬ 
cobi, that the eggs of fillies refill corruption and putre- 
faclion longer than moll of the foft parts ; they will re¬ 
main unchanged four or five days in the belly of a dead 
female; the ripe fpawn of a female trout which had been 
dead four days, and already ftank, was fprinkled with the 
milty liquor of a living male, and produced young trouts. 
Vol. X. Nq. 710. 
Y O LOG Y. 745 
The fame naturalift is of opinion, that the feminal fluid 
of the dead male will continue prolific as long as it pre- 
ferves its fluidity. See farther under the articles Mu- 
rvena and Rama. 
But fome fillies have a different mode of generation, 
and reproduftion. The female rays, (harks, fome of the 
blennies, and fome of the lilnres, do not lay eggs ; the 
ova are fecundated, nourilhed, and hatched, in the belly 
of the female; and the young are brought forth perfectly 
formed. Tliefe have been called viviparous animals ; but 
the term is not correct, as La Cepede obferves, for that 
word fiiould be confined to fuch animals as draw their 
nourifliment, or life, immediately from the body of the 
mother, which tliefe animals do not, being inclofed in an 
egg which precludes any communication with the body 
of the mother, whether the egg be hatched by heat within 
the body or previoufly excluded ; and he propofes the 
epithet of viparous to diftinguifn them, which lie lays can¬ 
not but bring to mind the production of vipers, which is 
effected in the lame manner. 
The eggs of the viparous fillies, then, are much larger in 
lize, but in fmaller number, as may be reafonably fup- 
poled, fince they are to attain their full fize and be hatched 
in the body of the mother ; in faft, they feldom exceed 
fifty. But, if thefe eggs, continually remaining in the 
belly of the female, contain living embryos, they mult 
have been fecundated in that place ; the prolific fluid of 
the male mu ft have penetrated to the ovaries. * Thus the 
males of thefe fpecies mult form an intimate and dole union 
with their females ; there muft he a real contafl, which 
mull continue till the feminal liquor is emitted ; and in 
fad it is known, that in fome fpecies, as the rays, (harks, 
chimera, &c. the male lias a kind of hooks or clafpers, 
with which he Lizes the female, confines her in the pro¬ 
per pofition, and prevents her efcape till the end is ac- 
complilhed. 
In fome fpecies, as the Syngnnthus and Silurus' afci- 
tus, the eggs as loon as formed are exciuded out of the 
body, and remain attached under the belly or under the 
tail, arid are hatched in that pofition. Thele fifties 
therefore muft couple like the rays and (harks, fince the 
eggs nluft be fecundated either within the body, or while 
attached to it. 
Wi.th a view to afcertain more corredly and latisfado- 
rily the progrefs of.generation in the finny tribes, that in¬ 
genious ichthyologift, Eliefer Bloch, procured the fpawn 
of different fillies from the Tides of rivers and lakes ; and, 
having no pond or piece of water at his command, he 
contrived, by artificial means, in his own houfe, to make 
the following experiments, which we lhall prefent to the 
reader in his own words. 
“ I procured from the river Spree fome aquatic plants, 
whereon the eggs or fpawn of the perch, bream, carp, 
trout, ,&c. had been voided. I brought them home in a 
little water ; I then put them into a veffel full of river- 
wateV, which was changed every day ; and at the end of 
feven days had the plealitre to fee the water enlivened by 
fome millions of linall filh. As the veffel had ftood in a 
room expofed to the rays of the fun, and as every piece 
of water may not have that advantage, I made the fol¬ 
lowing experiments. I put fome weeds whereon eggs had 
been voided into four tubs ; one I expoled to the mid¬ 
day fun, another to the morning fun, a third to the even¬ 
ing fun, and the fourth I placed where the fun could not 
reach it at all. On the feventh day I faw little fifties in 
the firft ; in the fecond and third they appeared on the 
eighth day ; .and in the fourth on the ninth. I have re¬ 
marked before, that all the eggs are not fecundated by 
the male; and it happened fometimes that of a hundred 
eggs which, were on a weed not one would be hatched ; 
whereas one little branch, which I put in a cup, furnilhed. 
about lixty young fry. But by means of a magnifying- 
glafs, I could determine whether the eggs are fecundated 
or not; in the former cafe, they always appear more 
tranfparent and yellow, which marks become more vifible 
9 D after 
