U R C 
*rhis fifh is commonly about feven or eight 
inches in length ; the head is large, bony, rough, 
and fquarifh ; and the body is long and rounded. 
The upper part is afh-coloured ; and the belly is 
white. The fcales, which are fmall and thin, 
are difpoled in oblique ranges acrofs the body of 
the fifh, running towards the tail. The face is 
fiat, and feems to be turned upwards ; and the 
eyes ane fmall and prominent, and fo placed in 
the upper part of the head, as naturally to look 
upwards whence the filh receives it's prefent 
name. 
Providence, indeed, feems wifely to have or- 
dered that the eyes of the Uranofcopus floould be 
thus fituated; for the fifh, keeping always at the 
bottom, muft look for it's food above it. How- 
ever, it is not the only inhabitant of the deep 
whofe eyes are placed in a fimilar manner j the 
rana pifcatrix, as well as fome others, have the 
fame manners, and enjoy the like advantages. 
URCHIN. An appellation by which many 
naturalifts exprefs the hedge-hog. 
URCHIN, SEA. A name by which ichthy- 
ologifts fometimes exprefs a genus of fifhes, of 
which there are many fpecies. 
The manner in which thefe creatures move at 
the bottom of the fea has frequently been the 
fubjeft of difpute among naturalifts. The gene- 
ral opinion has been, that their motion is effedled 
by means of their fpines or prickles, which ferve 
them inftead of legs; but fome have maintained, 
that the fpines of Urchins are of no ufe to them 
for this purpofe ; but that they move by means of 
certain legs, refembling thofe of the ftar-fifh, 
which they occafionally protrude or rctraft. 
Reaumur, however, who feems to have invefbi- 
gated the fubjefl with much accuracy, is of a 
contrary opinion. It is a faft, indeed, that tlie 
Sea-Urchin does throw out at the lower aperture 
ofit'sfhell, at pleafure, certain bodits flrongly 
refembling the legs of the ftar-fifh ; but thefe do 
not at all afiifl it's progreflive motion ; on the 
contrary, their real ufe is to keep the creature 
ftill, and fixed in the fame pofition : and, to de- 
fcribe thefe inftruments more exa6lly, they may 
be compared to the horns of fnails ; whence 
Reaumur has chofen rather to give them the ap- 
pellation of horns than legs. The ufe the Ur- 
chin makes of thefe horns, while in motion, is 
to feel about, and examine the ground on which 
it walks J and they are not only placed round tiie 
orifice of the fhell, but every where difperfed 
among the fpines, entirely over the furface of the 
fhell. 
All the fpines are capable of affifting the crea- 
ture in it's motions but it principally employs 
thofe near the mouth. When it has determined 
which way it fhall move, thofe fpines which fiiand 
diredly toward that point, and thofe which are 
immediately oppofite, are of equal fervice. It 
draws itfelf forward by means of the firft, and 
puihes itfelf on with the others : to efi^ecft this, it 
firft thrufts out the foremoft ones as far as pofTi- 
ble ; and, prelTing them againft the bottom, draws 
on it's body by their afllftancej and this is fuc- 
ceeded by drawing up the hinder ones clofe to 
it's fhell, and then fixing them likewife againft 
the bottom. 
• Such is the manner of this curious creature's 
marching in the common way v/ith it's mouth 
downward : but it polTeffes this fingularity, that 
it is not confined to that pollute alone in moving, 
U RT 
but can, with equal facility, walk widi it's mouth 
upwards, or run along fideways after the manner 
of a wheel, or in any intermediate direction. 
The legs and horns cover all parts of the animal ; 
and are in every part of it capable of moving' 
feparately thirteen hundred horns ; and upwards 
of two thoufand fpines, v.'hich ferve for ieo-s. 
URIBACO. A Brazilian fea-fifh, fomewhat 
of the figure of the pearch. It's back is ridged j 
it's belly is flightly prominent; and it's length is 
ufually ten or twelve inches. The teeth are 
fmall and fliarp ; the extremities of the gills and 
gill-fins terminate in a triangular point; the ven- 
tral fins are fupported by a very rigid and ftrong 
fpine; along fin, behind the anus', is fuftairud 
by flexile and fliort fpines; and the dorfd fin, 
which is of an equal breadth, and reaches nearly 
to the tail, is fupported by prickly rays. The 
tail is deeply bifid ; the fcales are of a fine filvcry 
whitenefs, with a faint caft of pale clear red ; tlie 
ventral fins are white ; and the dorfal fin and 
tail are reddifh. The lateral line is broad, 
and of a fine red colour ; and over and under 
it, near the tail, on each fide, there is a large 
black fpot. 
UROGALLUS MAJOR. See Cock oy 
THE Mountain, and Grouse. 
UROGALLUS MINOR. See Grouse. 
UROMASTIX. A name given by lomc 
naturalifts to that kind of lizard ufually denomi- 
nated cordvlus. 
VROWipISH. A frefh-water fiiTi of the 
malacoftomous or leather-mouthed kind, caught 
in the German lakes and rivers, and efteemed 
very delicate. It has fome refemblancc of the 
Englifli rudd ; but it's body is longer in propor- 
tion to it's breadth. The back is brown; the 
belly is yellow ; the ventral fins, near the anus, 
are a little reddifii ; and the refl are brown. The 
fcales are large and filvery ; in the lower part of 
the irides there is a blood-coloured fpot; and the 
tail is forked. 
The ufual fize of this fifh is feven or eight 
inches, though it is fometimes caught confider- 
ably larger. 
URSA. See Bear. 
URTICA ERRANS. A marine animal, re- 
fembling the common Urtica Marina in many 
particulars ; but as that is always fixed down to 
the rocks, this fpecies is always found ioofe. 
It has been generally fuppofed that thefe 
creatures affeft the flvin with a ftinging pain 
like nettles; but Reaumur, who faw prodigi- 
ous numbers of them on the coafts of Poiftou,, 
declares that he difcovered no fuch quality ia 
any of them, any more than in thofe fixed to 
the rocks. 
In fubftance, thefe animals nearly rcfemble a 
flifF jelly; and, if one of them be taken into the 
hand, it will fpeedily melt into clear water» 
Neverthelefs, they are true and perfefl animals, 
of various fpecies and colours; though their 
general figure may be exprelTed by tliat of the 
head of a large mufhroom: their upper '{v.y^ac^ is 
convex in the fame manner ; and this convexity 
is greater or lefs in the different kinds, as it is in 
the different fpecies of muflirooms. 
URTICA MARINA. A remarkable genus 
of aquatic animals ; fo called from a fuppoiition 
of their afFe6ling the f]<in, on touching them, 
with a painful fenfation like the ftinging of net- 
tles. Thefe are animals of the loweft ciais; and 
. have 
