408 
PLINX'S NATURAL HISTORY. 
[Book IX. 
the rhomlDus in the lateral position of the body. The rhombus 
lies with the right side upwards/^ while in the sea-sparrow the 
left side is uppermost. Some sea-fish, again, are long, as the 
mursena and the conger. 
CHAP. 37. — THE PINS OF PISH, AND THEIR MODE OP SWIMMING. 
Hence it is that there is a difference,^^ also, in the fins of 
fish, which have been giyen them to serve in place of feet, none 
having more than four,^^ some two only, and others none.^* 
It is in Lake Eucinus^^ only that there is a fish found that has 
eight fins^^ for swimming. Those fishes which are long and 
slimy, have only two at most, such, for instance, as eels and 
congers : others, again, have none, such as the mursena, which 
is also without gills.^^ All these fish^^ make their way in the 
sea by an undulatory motion of the body, just as serpents do 
on land ; on dry land, also, they are able to crawl along, and 
hence those of this nature are more long-lived than the others. 
Some of the flat-fish, also, have no fins, the pastinacse,^^ for in- 
stance — for these swim broad-wise — those, also, which are 
known as the ^^soft^' fish, such as the polypi, for their feet^^ 
serve them in stead of fins. 
55 The pleuronectes in general, Cuvier says, have the two eyes situate on 
the same side of the body. The turbot has them on the left side, and Hes 
on the sand on the right side, while the plaice or the flounder has the eyes 
on the right, and Hes on the left side — the reverse of what Pliny says. 
56 Aristotle, Hist. Anim. B. i. c. 6. 
57 By this Pliny means, Cuvier says, only the symmetrical fins, or pairs 
of fins, the pectoral namely, which are in place of arms, and the ventral, 
which are instead of feet ; of which, in fact, no fish has more than two 
pairs. Pliny does not include in this statement the dorsal, anal, and pec- 
toral fins. 
58 Eels and congers, for instance, which have but one pair. 
59 MursenaB and lampreys. 60 ggg [[[^ 17^ 
61 Cuvier thinks that there can be no question that he is speaking here 
of some mollusc or crustaceous animal. 
62 Muraense, like eels, have gills, but the orifice, Cuvier says, is much 
smaller than in the eel, and the opercula, under the skin, are so small as to 
be hardly perceptible ; indeed, so much so, that modern naturalists, Lacepede, 
for instance, have denied the fact of their existence. 
63 Aristotle, DePart. Anim. B. iv. c. 13, and Hist. Anim. B. i. c, 6. 
6* Or sting-ray. On the contrary, Cuvier says, the pastinaca, more than 
any other ray, has large pectoral fins, horizontally placed ; but they adhei'e 
so closely to the body that they do not appear to be fins, unless closely 
examined. 
65 By this name, Cuvier says, he calls the tentacles or feelers, which 
