55 
bristles, from whence the name. The common Chaeto- ROOM XI. 
dons ( Chcetodon ) have their opercular bones finely natThist, 
ciliated, while the Horny Chaetodons have the lower 
part of the operculum ending in a large spine. These 
fish are very numerous on the rocky shores of the seas 
of warm climates. They are generally beautifully and 
variously coloured, and good for food. Many are re¬ 
jected from prejudice, though the Sea Bream ( Brama ) 
has many of the characters of the Chaetodons, except 
that the palate is not toothed. 
The Scomberoid fishes have a smooth skin covered 
with a multitude of small scales, and a large caudal fin. 
They are much used as food, and afford great employ¬ 
ment to the fishermen. 
The Mackerel ( Scomber ) has two dorsal fins: the 
hinder rays of the posterior are separated from each 
other, forming a sort of series of small fins, as in the 
common Mackerel (, Scomber scombus ). Some of the 
species have a ridge of cartilaginous spines on the side 
of the tail. 
The Sword Fish ( Xiphias ) is very like the Tunny, 
but the front part of its upper jaw is produced into a 
long beak, by which it attacks the larger sea animals. 
It swims with excessive rapidity, and its flesh is much 
praised. The common Sword Fish (. Xiphias gladius) 
has no ventral fins. The Flying Sword Fish ( Notis - 
tium) has distinct ventral fins, and the dorsal very high 
and long, which enables it to swim with such velocity 
that it can drive its beak through the stout oak plank¬ 
ing of a ship. A fine specimen of this fish is in a 
Case over the Fire-Place, and by the side of it a 
piece of oak plank pierced by the beak of a larger fish 
of this species. The fish itself is very rare, yet seve¬ 
ral well recorded instances of similar occurrences are 
known. In many genera of the Scomberoid family, the 
spines, which in most fishes support the front dorsal 
fin, instead of being united together, are separate and 
free. This is the case with the Pilot Fish ( Gastev - 
Qsteus ductor ), and the Lichia ( Scomber glaucus )» 
The 
