136 Cycloid Acanthoptekes. FISHES. Scombeides. 
The genera are — Thyrsites; Gempylus; Lepidopus; TricTii- 
urus; Epinnula{Po&-f)-, Dicroto (Gunther); AphanopusiLovid)-, 
and Ruvetlus (Valenc^. 
The Scabbard-fish (Lejndopus argyreus) has been 
taken on the Devonshire coast, and is the only British 
member of the family. Young ones not more than 
ten inches in length have been seen, but the old fish 
exceeds five feet One of the latter was in the act of 
swimming in Salcombe harbour with amazing velocity, 
with its head raised out of the water, when it was 
killed by a blow from a fisherman’s oar. Ruvetlus pre- 
tiosus of Cocco is studded with bony spines on the body. 
Family XXIX. — SCOMBRTDES {Scomhridce). 
Plate 10, figs. 51, 52. 
The Scomberoid or Mackerel aspect of this family is 
easily recognizable, proving the assemblage to be a 
natural one. The Tunnies, which are its most active 
and powerful members, have bone-corpuscles in their 
skeletons, and thus form a transition to the Physos- 
tomes, whose bony framework is generally built up of 
true bone, and not merely of osteoid structure, like 
those of the 'Teleostomi, or Acanthopteres in general. 
The texture of the bones of the Scombrides is for 
the most part loosely fibrous, penetrated by an oily 
secretion, but with a small quantity of earthy matter 
compared to their extent of surface. This gives great 
lightness to the skeleton, and accords with the habits 
of the mackerel tribe, which live on the surface of the 
ocean, and delight in skipping into the air, such motions 
being effected by their strong caudal muscles, coloured 
in part with red blood. The tail at the setting on of 
the caudal fin, is much more slender than in other 
fishes, but tapers gradually from the fusiform or com- 
pressed body ; and the crescentic or swallow-tailed 
manner in which the fin expands, gives it much power 
as a propeller. In many species the sides of the tail 
are keeled, and they are also frequently protected by a 
ridge of scutiform pointed plates. 
The scales are in this family generally small, tender, 
and smooth ; sometimes lost in a shining nacry surface, 
as in the common mackerel. 
In most Scombrides the jointed portion of the dorsal 
fin is separated from the spines by a notch, or by a 
naked space, and the membranes are generally delicate, 
disappearing partially with age. Sometimes the spines 
of the dorsal stand singly, each with a small triangular 
membrane behind it, or without a membrane at all ; 
and not unfrequently the posterior tufted rays of the 
soft dorsal and anal are similarly isolated, in which 
case they receive the appellation of ‘‘ pinnules ” (fausses 
pinnules of Cuvier). In the majority of the genera, at 
least two of the anal spines are detached in front of 
that fin. Most generally the ventrals are situated 
under the pectorals, but in some rare instances they 
are absent. Some species have a short oblique cuta- 
neous crest on the base of each side of each lobe of the 
caudal fin. No armature exists on the opercular 
pieces of these fishes. The branchiostegals commonly 
number seven ; sometimes, however, there are no more 
than six, and in other instances they amount to eight. 
In the structure of the jaws, the Scombrides resemble 
the other Acanthopteres, in having the upper lip bor- 
dered wholly by the generally dentiferous premaxil- 
laries. The edentulous maxillaries lie in the membrane 
behind, and approach the corner of the mouth only 
when the jaws are widely extended. They are not 
serrated ; and a similar smoothness and absence of 
projecting angular points prevails in the heads of 
these fishes, which have very generally the form of 
compressed cones, adapted to swift motion through 
the water. 
The numerous pancreatic cseca are often so conjoined 
as to form a tolerably compact glandular mass. Most 
of the Scombrides have a larger and more complicated 
brain than the generality of fishes. The stomach is 
large and csccal, with folds of the internal membrane 
that greatly extend the surface. Some species have 
an air-bladder ; others, even in the same genus, want 
that organ. 
All these characters cannot be found in every 
member of the family, being variously combined in 
varying numbers in the different groups. The family 
as here restricted is less extensive, but more natural 
than it was as propounded by Cuvier, having been 
made so by the separation of some of his sections of 
genera. 
The genera axe — Scomber ; Thynnus; Auxis; Pelamys, 
Cybium ; Naucrates ; Elecate ; Eypsiptera ; Trachurus ; Caram 
gichthys; Caranx;* Argyreiosus ; Micropleryx (Agassiz); 
Seriola (Cuv.); Serioklla (Guichenot); SerioHchthys (Bhekery, 
Nauclerus ; Porihmeus ; Chorineyaus; Lichia; Temnodon; Tra- 
chinotus; Palinurus (Dekay or Pammelus, Gunther); Paropsis 
(Jenyns); Olistes; Scyris; Lactarius; Psenes; Nomeus; Ges- 
terochisma (Richardson); Cubiceps (Lowe); Neptomenus 
(Gunther); Platystetlius (id.) 
The British species are — the Mackerel {Scomber 
scombrus) ; the Spanish Mackerel {Sc. colias) ; the 
Dotted Mackerel {Sc. punctatus) ; the Tunny {Thynnus 
vulgaris)-, the Bonito {Th. pelamis); the Belted 
Bonito {Th. brachypterus) ; the Germon {Th, ala- 
longa) ; the Plain Bonito {Auxis vidgaris) ; the Pilot- 
fish {Naucrafes ductor) ; the Derbio {Lichia glaucus) ; 
and the Scad ( Trachurus vulgaris). 
The Scombrides are objects of fisheries, in the Medi- 
terranean and other seas, as extensive and important to 
the maritime populations there as the herring fisheries 
are in the north. The Tunny is one of the largest of 
marine fishes, since it attains the weight of one thou- 
sand pounds or more; when under three hundred 
pounds, it is termed by the Sards mezzo-tonno or “half- 
tunny.” Aristotle mentions one that weighed twelve 
hundredweight. The abundance of these fishes in 
the Bosphorus, is said to have been the origin of the 
name of Golden Horn applied to the port of Byzan- 
tium. The Tunny fi.shery was established in a very 
early age by the Phoenicians on the coasts of Spain, 
both on the Mediterranean and Atlantic sides of the 
peninsula, and the fish is represented on the medals of 
Carteja and Tartessus. 
The Tunny fishery of Sicily has been described in 
a spirited manner by Brydone and Dumas, to whose 
* Mcgalaspis, Decapterus, Sclav, Carangioides, Leioglossus, 
Uraspis Selaroides, Leptaspis, and Gnaihonodon, are dismem- 
berments of Caranx, which are not adopted in the catalogues 
of the British Museum by Dr. Gunther. 
