513 
O P II I 
the branchial cavity, or front getting out of that cavity 
through the branchial aperture. This confifts of a femi- 
lunar valve, attached to the front part.of the branchial 
aperture, which ftiuts it at the will of the animal by lying 
down on the pofterior part; this union of. the powers of 
an operculum, a membrane, and a valve, preventing the 
egrefs or regrefs of water, feems defcined by nature to 
makeup for the orifice of the mouth, which, according to 
Commerfon, cannot be (hut. The lateral line is hardly 
vifible ; the belly is carinated almoft in its whole length. 
ThepeCForal fins are fmall, tender, and tranfparent; they 
have a triangular fhape when fpread, and contain ten or 
twelve rays. The anal fin, which confifts of"fifteen foft 
rays or thereabouts, points backwards, and reaches almoft 
over the tip of the tail-fin, of which it feems to form a 
part;, the dorfal tin rifes lower upon the body than 
the anal, has the fame number of rays, is longer, and 
hangs over the tail-fin in the fame manner, but farther 
tlill; as each of thefe fins joins to the tail, the caudal fin 
appears like a trident, or as three tails, or three diltinCt 
parts of the fame tail, lienee the name triurus, or three¬ 
tailed. However, the tail-fin, properly fo called, is very 
fcanty, and, though compofed of twenty rays, might ra¬ 
ther be taken for the rudiments of a fin ; its rays are foft, 
peffinated, articulated, and much divided at their extre¬ 
mity ; fo that this fifn would have little ftrength for 
fwimming in a roug^i fea by the aid of its tail, were it 
not thus affifted by the peculiar fhape and direction of 
the dorfal and anal fins. The weight of the largeft of 
thefe nfh which Commerfon examined, was about four 
ounces. 
5. Ophidium aculeatum, the prickly ophidium : fnout 
pointed. There are 16 rays in each pectoral fin, 53 in 
the anal, 14 in the tail, and 31 in the dorfal. The body 
is long, and laterally comprefted. The head is fmall and 
narrow; the upper jaw is longer than the under; but 
there are noteeth ; the upper lip is lengthened out into a 
beak or trunk, in the manner of the preceding, but more 
acuminate. The eyes are fmall; pupil black, iris white. 
The gills have a wide aperture ; the cover is fingle, the 
membrane loofe. The vent is near the tail. The back 
is rounded. The fides are reddifh upwards, filvery to¬ 
wards the belly ; the belly white, and carinated. The 
ventral cavity is long. The lateral line is not far from 
the back, and equi-diftant from it all the way. The pec¬ 
toral fins are fhort, brown in the middle, and violet-co¬ 
lour in other parts ; the dorfal, which is oppofite the 
anal, is marbled red and brown, having two black fpots 
(fays Bloch) in yellow circles; but the number of thefe 
is not conltant, for Nieuhoff found five on the fpecimen 
he examined, and he called the fifli in confequence-w^wg’, 
five-eyes, becaufe the fpots look like a black pupil in a 
yellow iris: Willoughby and Ray have followed him in 
calling this fpecies pentophthulmos , which fignifies the 
fame thing; fb we may conclude five to be the moft ufual 
number. The fin of the tail is variegated blue and black, 
the anal is reddifh, with a dark border; before it are two 
fpines, and fourteen before the dorfal fin, all Handing 
apart and bent backwards. See the Plate, fig. 4. 
This fpecies is found in the frefh waters of the Eaft 
Indies ; the inhabitants make a delicate difli of it. Its 
nourifhment is worms and flime. It grows fix.or eight 
inches long, and is caught in nets. This is placed in a 
ieparate genus by Cepede, the Macrognathus, or long- 
fnout, and he has added the following fpecies under the 
fame head ; but Gmelin, from Bloch’s defeription, has 
received it into this genus in his edition of Linnaeus, for 
it was not noticed by Linnaeus himfelf. Gmelin indeed 
exprefl'es a doubt of its belonging to this genus, as it is a 
frefh-water fifn, and has no teeth. 
6. Ophidium armatum, the armed ophidium: fnout 
long, and 33 fpines before the dorfal fin. This fpecies is 
deferibed by Cepede from a dried fpecimen in a collection 
from Holland. It is much fmaller than the preceding, 
but is formed in the fame manner 5 the fnout, howeveV, 
Vol. XVII. No. 1194. 
D I U M. 
is not fo long in proportion, it exceeds the lower jaw by 
about half its length only ; and there are feveral rows of 
teeth in both jaws. There is a fpine near each eye, three 
at each operculum, and two before the anal fin. It is 
called armatum from the number of fpines which appear 
on the hack, amounting to thirty-three in a longitudinal 
row', each partly inclofed in a kind of (heath. The dorfal 
and anal fins do not Hand fo diftinCl from the caudal as 
in the preceding fpecies; they touch indeed, and can 
only be diflinguiflied by a fmall furrow in the membrane. 
It was not poflible to count the rays.in the fins; but the 
dorfal contained’ more than feventy, and each peCforal 
above twenty ; fo that the rays are more numerous than, 
in the preceding fpecies, if they were rightly reckoned by 
Bloch. Its country is not known. 
7. Ophidium meftacembalum, the Aleppo ophidium : 
fnout pointed, jaws equal. The firfi defeription of this 
fpecies feems to have been given by Dr. Alexander Ruffe], 
in his Natural Hiflory of Aleppo. It has fo much the 
general appearance of an eel, that, according to Dr. Ruffe], 
it’is confidered as fuch by the Europeans refident at 
A.leppo, where it is often brought to table, and eats like 
an eel, though fomewhat iefs fat. Its ufital length is 
from a foot to eighteen inches or more ; the head is ob¬ 
long, fubcylindric, narrower than the body, and con¬ 
tracted into ar fab-acuminate fnout in front; the eyes are 
fmall, lituated on each fide at no great diftance from the 
tip of the fnout; the nofinis are feated at fome difianc-e be¬ 
fore the eyes ; the mouth is fmall; the jaws are equal, with 
lax flefhy lips ; the teeth of moderate (ize, and fomewhat 
confufedly placed in both jaws ; the tongue and palate 
are fmooth ; the gill-covers finooth, the branchial aper¬ 
tures opening widely beneath; the gill-membrane five- 
rayed. The body anguilliform, and marked down the 
back, as far as the beginning of the dorfal fin, by a row 
of about thirty-two fmall (harp fpines, fet at equal difiances, 
and each recumbent in a fmall furrow, from which it is 
eligible at the pleafure of the animal; the dorfal fin com¬ 
mences at about two-thirds of the length of the body 
from the head, is of moderate width, and is continued 
into the tail and vent fin in the manner of thofe of an eel; 
the anal fin running beneath to about the fame diftance 
with the dorfal above : at the origin of the anal fin are 
two ftrong fhort fpines, and at a little diftance farther on 
the abdomen is a third; the peCtoral fins are very fmall, 
and rounded ; the lateral line is pretty ftrongly marked, 
and runs from the top of the gills along the middle of the 
body to the tail. The whole body is covered with fmall 
feales, like thofe of an eel; the colour on the upper parrs 
is a clouded variegation of vvhitifliand rufous, the under 
parts being entirely white; it is principally taken in the 
river Kowick near Aleppo. 
8 . Ophidium m-ucronatum, the ferrated ophidium : a 
ftrong denticulated lamina on each fide of the upper jaw. 
The pectoral fins have 12 rays each, the dorfal 6 or 7, the 
anal 80, the tail 19. 
This very Angular fifli was part of a collection fent from 
Cayenne to Paris ; Cepede makes a feparate genus of it, 
the Odontognathus, or “fifli with ferrated jaws.” No¬ 
thing like it had been deferibed hitherto. The head, body, 
and tail, are much compreffed. The lower jaw is the 
longeft, and rifes over the upper when the month is en¬ 
tirely (hut, fo as to be almoft vertical; it falls like a draw¬ 
bridge when the mouth opens; and then appears boafc- 
thaped, fcaiy, very transparent, furrowed underneath, 
and obfeurely ferrated on the margin. The lower jaw in 
falling brings forward two long flat pieces, of a fcaiy fub- 
ftance, which are faftened to the higheft part of the upper 
jaw; they are of a curved fhape, ftiarp at the points, and 
-ferrated like a faw all along their upper part; when they 
are drawn to their lowed point, the orifice of the mouth 
appears formed by the lower jaw, as (een between thefe 
two productions taken as the fides of the upper. While 
the mouth remains open, thefe laminae reach beyond the 
tower jaw ; but, upon the riling of the lower jaw to ihut 
6 P the 
