Chapter XXI: The Fishes of the Deep Sea (11)

One genus and species only (_Gonorhynchus greyi_) is known; it is a semi-pelagic fish, not very rare off the Cape of Good Hope, and in the Australian and Japanese seas. From 12 to 18 inches long. The colonists in New Zealand name it “Sand-eel,” as it frequents bays with sandy bottom. It is eaten.

NINETEENTH FAMILY--HYODONTIDÆ.

_Body covered with cycloid scales; head naked; barbels none. Margin of the upper jaw formed by the intermaxillaries mesially, and by the maxillaries laterally, the latter being articulated to the end of the former. Opercular apparatus complete. Adipose fin none; the dorsal fin belongs to the caudal portion of the vertebral column. Stomach horseshoe-shaped, without blind sac; intestine short; one pyloric appendage. Pseudobranchiæ none; air-bladder simple. Gill-openings wide. The ova fall into the abdominal cavity before exclusion._

One genus and species only (_Hyodon tergisus_) is known, generally called “Moon-eye.” It is abundant in the western streams and great lakes of North America. From 12 to 18 inches long.

TWENTIETH FAMILY--PANTODONTIDÆ.

_Body covered with large cycloid scales; sides of the head osseous. Margin of the upper jaw formed by the single intermaxillary mesially, and by the maxillaries laterally. The dorsal fin belongs to the caudal portion of the vertebral column, is short, opposite and similar to the anal. Gill-openings wide; gill-covers consisting of a præoperculum and operculum only. Branchiostegals numerous. Pseudobranchiæ none; air-bladder simple. Stomach without coecal sac; one pyloric appendage. Sexual organs with a duct._

A small freshwater-fish (_Pantodon buchholzi_), singularly alike to a Cyprinodont, from the west coast of Africa.

TWENTY-FIRST FAMILY--OSTEOGLOSSIDÆ.

_Body covered with large hard scales, composed of pieces like mosaic. Head scaleless; its integuments nearly entirely replaced by bone; lateral line composed of wide openings of the mucus-duct. Margin of the upper jaw formed by the intermaxillaries mesially, and by the maxillaries laterally. The dorsal fin belongs to the caudal portion of the vertebral column, is opposite and very similar to the anal fin; both approximate to the rounded caudal (with which they are abnormally confluent). Gill-openings wide; pseudobranchiæ none; air-bladder simple or cellular. Stomach without coecal sac; pyloric appendages two._

Large freshwater-fishes of the tropics, whose singular geographical distribution has been noticed above (p. 223).

OSTEOGLOSSUM.--Cleft of the mouth very wide, oblique, with the
lower jaw prominent. A pair of barbels at the lower jaw. Abdomen
trenchant. Bands of rasp-like teeth on the vomer, palatine and
pterygoid bones, on the tongue and hyoid. Pectoral fins elongate.

_O. bicirrhosum_ from Brazil and Guyana, _O. formosum_ from Borneo and Sumatra, _O. leichardti_ from Queensland.

ARAPAIMA.--Cleft of the mouth wide, with the lower jaw
prominent; barbels none. Abdomen rounded. Jaws with an outer
series of small conical teeth; broad bands of rasp-like teeth
on the vomer, palatines, pterygoids, sphenoid, os linguale, and
hyoid. Pectoral fins of moderate length.

The largest freshwater Teleostean known, exceeding a length of 15 feet and a weight of 400 pounds. It is common in the large rivers of Brazil and the Guyanas, and esteemed as an article of food. When salted it is exported in large quantities from the inland fisheries to the seaports.

HETEROTIS.--Cleft of the mouth rather small, with the jaws
subequal; barbels none. A single series of small teeth in the
jaws; pterygoids and hyoid with a patch of small conical teeth;
none on the vomer or palatines.

This fish (_H. niloticus_), which is not uncommon in the Upper Nile and the West African rivers, exhibits several anatomical peculiarities. The fourth branchial arch supports a spiral accessory organ, the function of which is still unexplained. The air-bladder is cellular, and the stomach consists of a membranous and a muscular portion.

TWENTY-SECOND FAMILY--CLUPEIDÆ.

_Body covered with scales; head naked; barbels none. Abdomen frequently compressed into a serrated edge. Margin of the upper jaw formed by the intermaxillaries mesially, and by the maxillaries laterally; maxillaries composed of at least three movable pieces. Opercular apparatus complete. Adipose fin none. Dorsal not elongate; anal sometimes very long. Stomach with a blind sac; pyloric appendages numerous. Gill-apparatus much developed, the gill-openings being generally very wide. Pseudobranchiæ generally present. Air-bladder more or less simple._

The family of “Herrings” is probably unsurpassed by any other in the number of individuals, although others comprise a much greater variety of species. The Herrings are principally coast-fishes, or, at least, do not go far from the shore; none belong to the deep-sea fauna; scarcely any have pelagic habits, but many enter or live in fresh waters communicating with the sea. They are spread over all the temperate and tropical zones. Fossil remains of Herrings are numerous, but the pertinence of some of the genera to this family is open to serious doubts, as the remains are too fragmentary to allow of determining whether they belong to Salmonoids or Clupeoids. Therefore, Agassiz comprised both families in one--_Halecidæ_. Many of the remains belong to recent genera, which are readily recognised, as _Clupea_, _Engraulis_ and _Chanos_, principally from the schists of Glaris and Licata, from Monte Bolca and the Lebanon. Others, like _Thrissopater_, from the Gault at Folkestone, _Leptosomus_, _Opisthopteryx_, _Spaniodon_, from the chalk and tertiary formations, can be readily associated with recent genera. But the majority do not show an apparent affinity to the present fauna. Thus, _Halec_ from the chalk of Bohemia, _Platinx_ and _Coelogaster_ from Monte Bolca, _Rhinellus_ from Monte Bolca and Mount Lebanon, _Scombroclupea_, with finlets behind the anal, from the Lebanon and Comen, and _Crossognathus_ from tertiary Swiss formations, allied to _Megalops_, _Spathodactylus_ from the same locality, and _Chirocentrites_ from Mount Lebanon, etc. Finally, a genus recently discovered in tertiary formations of Northern Italy, _Hemitrichas_, has been classed with the Clupeoids, from which, however, it differs by having two short dorsal fins, so that it must be considered, without doubt, to be the representative of a distinct family.

ENGRAULIS (including CETENGRAULIS).--Scales large or of moderate
size. Snout more or less conical, projecting beyond the lower
jaw. Teeth small or rudimentary. Intermaxillaries very small,
hidden; maxillary long, attached to the cheek by a scarcely
distensible membrane. Anal fin of moderate or great length.
Branchiostegals short, from nine to fourteen in number.

Not less than forty-three different species of “Anchovies” are known from temperate and tropical seas. They exhibit marked differences in the length of their maxillary bone, which sometimes does not reach the gill-opening, whilst in other species it extends far beyond it; and in the number of their anal rays, which varies from 20 to 80. Some have the upper pectoral ray prolonged into a filament, thus leading towards the succeeding genus, _Coilia_. The majority are recognised, besides, by their peculiar structure, by a broad silvery, lateral band, similar to that observed in the Atherines. The most celebrated Anchovy is _E. encrasicholus_, very plentiful in the Mediterranean, but rarely wandering northwards. It is the species which, preserved in salt, is exported to all parts of the world, although similarly lucrative fisheries of Anchovies might be established in Tasmania where the same species occurs, in Chile, China, Japan, California, at Buenos Ayres, each of which countries possesses Anchovies by no means inferior to the Mediterranean species.

COILIA.--Body terminating in a long tapering tail. Scales of
moderate size. Snout and jaws as in _Engraulis_. Anal fin
exceedingly long, confluent with the caudal. The two or three
upper pectoral rays are much prolonged, and their branches form
four, six, or seven filaments.

Ten species from Indian and Chinese seas.

CHATOËSSUS.--Body compressed; abdomen serrated. Scales of
moderate size. Snout obtuse, or obtusely conical, more or less
projecting beyond the cleft of the mouth, which is narrow, more
or less transverse. Maxillary joined to the ethmoid, its upper
portion being behind the intermaxillary. Teeth none. Anal fin
rather long; dorsal opposite to the ventrals, or to the space
between ventrals and anal. Gill-membranes entirely separate;
branchial arches forming two angles, one pointing forward and
the other backwards; the fourth branchial arch with an accessory
organ; branchiostegals of moderate length, five or six in number.

Ten species from the coasts, brackish and fresh waters of Central America (one species ranges to New York), Australia, the East Indies, and Japan.

CLUPEA.--Body compressed, with the abdomen serrated, the
serrature extending forwards to the thorax. Scales of moderate
or large, rarely of small size. Upper jaw not projecting beyond
the lower. Cleft of the mouth of moderate width. Teeth, if
present, rudimentary and deciduous. Anal fin of moderate extent,
with less than thirty rays; dorsal fin opposite to the ventrals.
Caudal forked.

This genus comprises more than sixty different species, the geographical distribution of which coincides with that of the family. The majority are of greater or less utility to man, but a few tropical species (_C. thrissa_, _C. venenosa_, and others) acquire, probably from their food, highly poisonous properties, so as to endanger the life of persons eating them. The most noteworthy species are--

1. _C. harengus_ (the “Herring”).--It is readily recognised by having an ovate patch of very small teeth on the vomer. D. 17–20. A. 16–18. L. lat. 53–59. Vert. 56. Gill-cover smooth, without radiating ridges. It inhabits, in incredible numbers, the German Ocean, the northern parts of the Atlantic, and the seas north of Asia. The Herring of the Atlantic coasts of North America is identical with that of Europe. A second species has been supposed to exist on the British coast (_C. leachii_), but it comprises only individuals of a smaller size, the produce of an early or late spawn. Also the so-called “White-bait” is not a distinct species, but consists chiefly of the fry or the young of herrings, and is obtained “in perfection” at localities where these small fishes find an abundance of food, as in the estuary of the Thames.

[Separate accounts on the Herring may be found in Cuvier
and Valenciennes, “Hist. nat. des Poissons,” vol. xx.; J.
M. Mitchell, “The Herring, its Natural History and National
Importance,” Edinb. 1864, 8vo; P. Neucrantz, “De Harengo,”
Lübeck, 1654; J. S. Dodd, “Essay towards a Natural History
of the Herring,” Lond. 1768, 8vo; Bock, “Versuch einer
vollstændigen Natur-und Handels-Geschichte des Hærings,”
Königsberg, 1769, 8vo.]

2. _C. mirabilis._--The Herring of the North Pacific.

3. _C. sprattus._--The “Sprat.” Without vomerine teeth. D. 15–18. A. 17–20. L. lat. 47–48. Vert. 47–49. Gill-cover, smooth, without radiating ridges. Abundant on the Atlantic coasts of Europe.

4. _C. thrissa._--One of the most common West Indian fishes, distinguished by the last dorsal ray being prolonged into a filament. Hyrtl has discovered a small accessory branchial organ in this species.

5. _C. alosa._--The “Shad” or “Allice Shad,” with very fine and long gill-rakers, from 60 to 80 on the horizontal part of the outer branchial arch, and with one or more black lateral blotches. Coasts of Europe, ascending rivers.

6. _C. finta._--The “Shad” or “Twaite Shad,” with stout osseous gill-rakers, from 21 to 27 on the horizontal part of the outer branchial arch, and spotted like the preceding species. Coasts of Europe, ascending rivers, and found in abundance in the Nile.

7. _C. menhaden._--The “Mossbanker,” common on the Atlantic coasts of the United States. The economic value of this fish is surpassed in America only by that of the Gadoids, and derived chiefly from its use as bait for other fishes, and from the oil extracted from it, the annual yield of the latter exceeding that of the whale (from American Fisheries). The refuse of the oil factories supplies a material of much value for artificial manures.

[See G. Brown Goode, “The Natural and Economical History of the
American Menhaden,” in U.S. Commission of Fish and Fisheries,