Chap. 33.] 
riSHES. 
405 
CHAP. 33. GILLS AND SCALES. 
Some fishes have numerous gills, others again single^® ones, 
others double ; it is by means of these that they discharge the 
water- that has entered the mouth. A sign of old age^^ is the 
hardness of the scales, which are not alike in all. There are 
two lakes of Italy at the foot of the Alps, called Larius and 
Verbanus, in which there are to be seen every year, at the 
rising of the Yergiliae,^^ fish remarkable for the number of their 
scales, and the exceeding sharpness*^ of them, strongly resem- 
bling hob-nails in appearance ; these fish, however, are only 
to be seen during that month, and no longer. 
38 He must mean single ones, on each side of the head. Cuvier remarks, 
that the present passage is from a longer one in Aristotle, Hist. Anim. B. 
ii. c. 13, which, however, has come down to us in such a corrupt and frag- 
mentary state, that it is totally unintelligible, or, at all events, does not cor- 
respond with modern experience. No fish, he says, is known to us that 
has one or two gills only. The Lophii of the system of Linnaeus have three 
gills on each side, and the greater number of fish four, with a half one at- 
tached to the opercule. Some cartilaginous fish, again, have five or six, 
and the lampreys seven. 
29 Aristotle, Hist. Anim. B. iii. c. 10. 
40 The modern Lago di Como, and Lago Maggiore. See B. iii. c. 23. 
*i See c. 20, as to the Yergilise. 
*2 Cuvier says, that in various species of the cyprinus, and more especially 
the rubellio, the Cyprinus rutilus of Linnaeus, the roach, the Cyprinus jeses 
of Linnaeus, and the bream, the Cyprinus brama of Linnaeus, the male has, 
during the spawning season, little warts adhering to the skin and scales. 
This appearance has been remarked in especial on a species found in the 
lakes of Lombardy, known there as the pigo," and similar to the roach 
of other countries. It is most probable that it is to this appearance that 
Pliny alludes. Eondelet, in his book on Fishes, gives a representation of 
it, and calls it " pigus,"or " cyprinus clavatus but he wrongly, like Pliny, 
takes it to be a peculiar genus of fish. 
" Clavorum caligarium" — "nails for the caliga." This was a strong, 
heavy sandal, worn by the Roman soldiers. It was worn by the centurions, 
but not by the superior officers ; and from the use of it, the common sol- 
diers, including the centurions, were distinguished by the name of cali- 
gati." The Emperor Caligula received that cognomen when a boy, in con- 
sequence of wearing the " caliga," and being inured to the life of a common 
soldier. The hob-nails with which the "caliga" was studded are men- 
tioned again in B. xxii. c. 46, and B. xxxiv. c. 41. Josephus tells us of 
the death of a Boman centurion, which was occasioned by these nails. As 
he was running over the marble pavement of the temple of Jerusalem, his 
foot slipped, and he was unable to rise, upon which he was overpowered 
by the Jews, and slain. After the decline of the Boman empire, the caliga 
was no longer worn by the soldiers, but was assumed by the monks and re- 
cluses. 
Dalechamps says, that in a similar manner, in the lake known by the 
