T R O 
TRISET.gi. A term by which foine wHtm 
on infefls exprefs a certain genus of the feticauds, 
or brillle- tailed flies; diftinguiOTcd from the reft 
by having three hairs or briftles proceeding from 
the tail. 
TRISEUS. An appellation by which fome 
ichthyologifts exprefs that fpecies of gadus more 
ufually denominated the muftela fluviatilis, or eel- 
pout. 
TRITON. In the Linnsan fyftem, a genus 
of the mollufca order of worms: the charaftersof 
which are; that the body is oblong, and the tongue 
fpiral; and that the tentacula are twelve in num- 
ber and bipartite, fix on each fide, ajid the three 
hinder ones cheliferous. 
There is only one known fpecies, found in the 
clifts of fubmarine rocks. 
TRITON AVIS. A name by which Nie- 
remberg ha? defcribed a Weft Indian bird famous 
for it's mufical qualities. It is faid to hare three 
diftinft notes; and to be able to give breath to 
founds of all the three kinds at the fame time. 
It is alfo much celebrated for it's beauty. 
TROCHILUS. In the Linnjean fyftem, a 
genus of the pica;, comprehending the polytmus 
and mellifuga of Briftbn ; the former including 
fixteen, and the latter twenty fpecies. See Hum- 
MING-BlRD. 
Trochilus is alfo an appellation ufed by Ari- 
ftotle, and other ancient naturalifts, for the regu- 
lus criftatus, or golden-crowned wren. 
Trochilus is likewife the name of a remark- 
able, aquatic bird, called Corriza by the Spa- 
niards. It is defcribed by Aldrovandus as being 
very long-legged, yet web-footed. It's beak is 
ftraight, and black at the end ; and the opening of 
the mouth is very wide. The under part is 
white; and the back, fhoulders, and wings, are 
ferruginous. It runs fwiftly. 
TROCHUS.- An appellation by which fome 
conchologifts exprefs a genus of fliells; fome fpe- 
cies of which refemble the Trochus or top. How- 
ever, as the fpecies are numerous, many of them 
bear very little refemblance to the plaything from 
which they receive their name: a late French 
writer has therefore more aptly charafterized the 
genus by calling it Cochlea ore depreffo. 
According to Linn?eus, the charafters of this 
•genus are the following;: the inclofed animal is a 
Aug; the fliell is univalve, fpiral, and conical; 
the aperture is fubtetragonous, angular, or round- 
ifh; and the columella or axis is oblique. He 
enumerates twenty-fix fpecies. 
The Trochlor Tops conftitute the fifteenth fa- 
mily of ftiells in Da Cofta's ingenious arrange- 
ment. He defines them to be fhells of a conic or 
pyramidal fliape, the top being broad and flattifli, 
and gradually tapering thence to a very narrow 
point; and the aperture or mouth generally angu- 
lar, low, and narrow. 
This is a numerous family; and confifts of many 
beautiful and curious fnells. 
TP..OCTUS. An appellation by whicli Ari- 
ftotle, and other ancient writers, exprefs a fpecies 
of fcomber ; diftinguifhed from others of the I<ind 
by the name of the fcomber Vv'ith two dorfal fins, 
and the laft ray of the hinder fin very long. 
TROGLODYTES. A term by which the 
wren is fometimes expreficd. 
TROGON, Curucui* A genus of the picas: 
the charadcrs of which arc; that the bill is fliorter 
fhan the head, cultrated, hooked, and ferrated at 
the margin of the mandibles; and that the feet 
are formed for climbing, having two toes forward^ 
and two backward. There are three fpecies of 
this genus; one of which is the Curucui of Brazil. 
TROMBETTA. An Italian appellation for 
the fcolopax of fome ichthyologifts. See Trum- 
pet-Fish. 
TROUT. A well-known valuable river-fifti : 
the diftinguifhing charadlers of which are; that 
the body is long; the head ftiort and roundifh; 
the extremity of the fnout obtufe and blunt; the 
tail very broad ; the mouth large ; and each jaw 
furnifhed with a fingle row of (harp teeth: that in 
the palate there are three parcels of teeth, each of 
an oblong figure in the congeries, all meeting in 
an angle near the end of the nofe; that the tongue 
alfo is furnifhed with fix, eight, or ten teeth; and 
the fides beautifully variegated with red fpots. 
It is worthy of obfervation, that this fifh, fo uni- 
verfally diffeminated, is unnoticed by any of the 
ancients; except Aufonius; and it is alfo equally 
Angular, that fo delicate a fpecies fhould be ne- 
gledled at a time when epicurifm was arrived at 
an excefs which it never can furpafs. 
The colours of the Trout, and it's fpots, vary 
greatly in different waters, and in different feafons; 
yet all maybe reduced to one fpecies. In Llvn- 
divi, a lake of South Wales, there are Trouts de- 
nom.inated coch y dail, marked with large red 
and black fpots ; others are unfpotted, and of a 
reddifh hue, that fometimes weigh near ten 
pounds, but their flefh is little efteemed. In 
Lough Neagh, in Ireland, there are Trouts called 
buddaghs, fome of which weigh thirty pounds; 
others of a much fuperior fize are taken in Hulfe- 
water, a lake in Cumberland, fuppofed to be of 
the fame kind with the Trouts in the Lake of 
Geneva; and in theRiverEnyion, in North Wales, 
there is a variety of the Trout, having a remark- 
able obliquity near the tail. 
It has been remarked that the ftomachs of 
common Trouts are uncommonly thick and muf- 
cular ; as they feed on the fliell-fifh of lakes and 
rivers, as well as fmall fifh ; and fwallow gravel 
or fmall ftones, for the purpofe of comiTiinuting 
the teftaceous parts of their food. The Trouts 
of certain lakes in Ireland are remarkable for the 
thicknefs of their ftomachs, which, from fome 
flight refemblance to the organs of digeftion in 
birds, are called gizzards; and the fpecies that 
contain tliem. are called gillaroo, or gizzard 
Trouts. However, from the obfervations made 
by Dr. Watfon and Mr. Hunter, there feems to 
be no reafbn for confidering the ftomachs of thefe 
Trouts as gizzards, but as true ftomachs. That 
of the Engliflj Trout is of the fame nature with 
the ftomach of the gillaroo Trout, except that it's 
coat is only about one-third as thick ; a circum- 
ftance that fccms to arife from, the natuie of the 
waters in which the different varieties refide. 
Thefe ftomachs are fometimes ferved up at table 
in Ireland under the name of gizzards, 
Trouts are extremely voracious, and afford ex- 
cellent diverfion to the angler. They fhift their 
quarters when about to fpawn ; and, like falmon, 
aiake towards the heads of rivers, in order to de- 
pofit their roes. The undcr-jaw of the Trout is 
fubjeft, at certain times, to the fame curvature as 
that of the falmon. 
Trout, White. Pennant has defcribed a 
fpecies under this appellation, which migrates 
from the fea into the River Efk, in Cumberland, 
from 
