759 f C H 
thefe veffels are more eafily diftinguiflied from the ureters, 
which convey the urine from the kidneys into the blad¬ 
der, and are fituated near the feminal vefl'els on each fide 
of the fpine; which, without attention, may be miftaken 
for the ovaries, efpecially when thefe laft are empty. The 
time leaft proper for this operation is juft after they have 
fpawned, becaufe the fifh are then too weak and languid 
to bear with fuccefs, fo fevere an operation ; however, 
with (kill and care, it maybe performed almoft at any time. 
V/hen a fifli is to be caftrated, it mult be held in a wet 
cloth, with its belly upwards ; then with a Iharp pen¬ 
knife, having its point bent backwards, the operator cuts 
- through the integuments of the rim of the belly, taking 
care not to wound any of the inteftines. As i'oon as a 
(mail aperture is made, he carefully inferts a hooked pen¬ 
knife, and with this dilates the aperture from between 
the two fore-fins almoft to the anus. He then, with two 
fmall blunt filvet-hooks, five or fix inches long, and of this 
form r, by the help of an afliftant, holds open the belly 
of the fifti ; and, with a fpoon or fpatula, removes care¬ 
fully the inteftines from one fide. When thefe are re¬ 
moved, yon tee the ureter, a fmall veflel, nearly in the 
direftion of the fpine, and alfo the ovary, a larger vefi'el, 
lying before it, nearer the integuments of the belly. 
This laft veflel is taken up with a hook of the fame kind 
with thofe before mentioned, and, after detaching it from 
the fide far enough for the purpofe, divided tranfverfely 
with a pair of (harp fciflars, care being taken that the in¬ 
teftines are not wounded or injured. After one of the 
ovaries has been divided, the operator proceeds to divide 
the other in the fame manner ; and then the divided in¬ 
teguments of the belly are fewed with lilk, the ftitches 
being inferted at a fmall diftance from one another. When 
the fifti are caftrated, they are put into the water where 
they are intended to continue; and they take their chance 
in common with other fifti, as though they were not caf¬ 
trated. With tolerable care, few die of the operation. 
-Phil. Tranl'. vol. xlviii. Part. 2. art. 106. Although we 
could not properly avoid inferring the above detail, it is 
prefumed that few will be pleafed with the invention. The 
operation is peculiarly cruel, and the purpofe of it only a 
piece of Apician refinement. 
Another method of improving the breed of fifties ftiould 
not be omitted, which is by crofting the genera or fpe- 
cies; it is well kno vn, that the lamb, the bull, the horfe, 
and the afs, have been ameliorated and brought to their 
prefent ftate of perfection by fuch means. Thus we fecun¬ 
date the fpawn of one fet of females with the milt of a 
different kind of males; the mules or mongrels thus pro¬ 
duced will be of a better fort than either of the tribes em¬ 
ployed, as in chemiftry the intimate combination of two 
fubftances will produce amals that fliall exceed in weight 
. the two bodies taken together in their natural ftate. But this 
muff not, in either cafe, be taken for a general rule; every 
intermixture cannot be expected to fucceed. Many pre¬ 
cautions muff be tiled: and therefore we (hall purlue this 
Curious fubjeft a little farther. 
The mules produced from different genera cannot be 
sxpe&ed to be fruitful; but, by only crofting the breed 
of the fpecies, we may greatly improve them in fize and 
other qualities, which will become permanent, and be 
tranlinitted to future generations ; they will be, properly 
fpcaking, new fpecies, fuch as nature accidentally pro¬ 
duces. In coupling the different fpecies of fifties, we have 
none of, thofe difficulties to encouter which impede our 
endeavours in pairing of birds or beafts. Fix upon the 
two fpecies which fpawn about the fame time, or where 
the fpawning of the one ends when the other’s begins. 
If the feminal liquor of the males is not eafily to be pro¬ 
cured at the proper time, collet the fpawn of the females, 
and place it at a proper depth in the water frequented by 
the males with which you mean to crofs the breed. Lay 
it fo that its odour may attraft thofe males, and in fuch 
a poiltion as may invite them to caff their milt in that 
place. Sometimes it will be neceflary previoufty to deftroy 
i e h 
or remove the fpawn of their own females in that quarter. 
Compofitions or paftes to attract them might be contrived 
after a few experiments. The carp and the criician are 
often naturally crofted in the breed ; and many other fpe- 
eies of the’Cyprinus might be improved by care and at¬ 
tention. This gives rife to an important refieftion on the 
generation of fifties, and indeed of inoft animals. 
Authors of great celebrity have afierted, that, in the 
production of fifties, the female had fuch an undivided 
influence, that the fetus was entirely formed in the egg 
before the emiffion of the male’s fecundating liquor; fo 
that this liquor could only be confidered as a ftimulus to 
give motion and life to the pre-exifting embryo. But this 
hypothefis, which has been fo extended as to become a 
general theory in the generation of animals, and even of 
man, is quite overturned by the aCtual production of 
mules in various animals, which have accidental refem- 
blances both to male and female. The experiment of 
crofting breeds may be made on a fmall fcale in a pond, 
by only catching a male full of milt, and gently ft robing 
his belly fo as to prefs out the feminal liquor upon the 
fpawn previoully (lied by your females ; even if the male 
ftiould be dead, provided he be opened direflly, the feed 
may be taken out and l'pread upon the water; and it will 
ftill be found fruitful. 
Thofe who buy fifb for the table ftiould be aware, that 
there is a method of blowing jifh, a practice fimilar to that 
of blowing flefti, poultry, and pigs, and adopted for the 
fame deceitful purpofes. The method of blowing fifti, ef¬ 
pecially cod and whitings, is by placing the end of a quill 
or tobacco-pipe at the vent, and pricking a hole with a 
pin under the fin which is next the gill; thereby making 
the fifti appear to the eye large and full, which when drefted 
will be flabby, and little elle than (kin and bones. But 
this impofition may be difeovered by placing the finger 
and thumb on each fide of the vent, and fqueezing it 
hard ; the wind may be perceived to go out, the (kin will 
fall in, and the fifti appear lank, and of little value. 
In the pofthumous papers of Mr. Hooke, a method is 
deferibed of gilding live craw-fifti, carps, &c. without in¬ 
juring the fill). The cement for this purpofe is prepared, 
by putting fome burgundy-pitch into a new earthen pot, 
and warming the veflel till it receives fo much of the 
pitch as will (tick round it; then ftrewing fome finely- 
powdered amber over the pitch when growing cold, adding 
a mixture of three pounds of linfeed oil and one of oil of 
turpentine, covering the veflel, and boiling them for an 
hour over a gentle fire, and grinding the mixture as it is 
wanted, with fo much pumice-ftone in fine powder as will 
reduce it to the confidence of paint. The fifti being wiped 
dry, the mixture is fpread upon it; and the gold-leaf being- 
then laid on, and gently preffed down, the fifth may be im¬ 
mediately put into the water again, without any danger 
of the gold coming oft', for the matter quickly grows firm 
in water. 
For a view of the great importance of fifiieries to the 
profperity of a country, fee the article Fishery, vol. vii. 
p. 406-419 ; for inftrudrions in angling, fee Fishing ; and 
for the moft approved methods of breeding fifth, fee Fish¬ 
pond, in the lame volume. 
ICHTHYOM'ANCY, f [of a fifti, and 
Gr. divination.] Divination by the entrails o’ fifties; for 
which Tirefias is fa id to have been famous. 
ICHTHYOME'THIA, / in botany. See Piscidia. 
ICHTHYOPH'AGI, /. [from fifti, and <p K 7 eiy, 
to eat.] Fish-eaters, a name given to a people, or rather 
to feveral different people, who lived wholly on fifti. The 
Ichthyophagi fpoken of by Ptolemy are placed by Sanfon 
in the provinces of Nanquin and Xantong. Agatharcides 
calls all the inhabitants between Carmania and Gedrofia 
by the name of Ichthyophagi. From the accounts given us 
of the Ichthyophagi by Herodotus, Strabo, Solinus, Plu¬ 
tarch, See. it appears indeed that they had cattle, but that 
they made no ufe of them, excepting to feed their ffth 
withal. They made their houtes of large filh-bones, the 
1 ribs 
