About the Work
The Class Pisces is a systematic natural-history treatise on fishes, arranged by Baron Georges Cuvier with supplementary additions by Edward Griffith and Lieutenant-Colonel Charles Hamilton Smith, and published in London by Whittaker and Co. It belongs to that great nineteenth-century genre of descriptive zoology in which the whole animal kingdom was sorted, named, and anatomically explained for an educated reading public. The volume opens with a title page and a list of plates—engravings numbered XXXII through LXII, keyed to facing pages, with additional entries for such creatures as the Australian remora and the dory—and then proceeds without preamble into the business of classification. Its subject is the fourth class of vertebrated animals, the fish, treated first as a single anatomical idea and then broken down, order by order and family by family, into its countless living forms.
“The tunny fishery was still more ancient in the West.”
The book is not a narrative and makes no pretence of being one. It is a catalogue in the fullest sense: a reasoned inventory in which every genus is defined by its teeth, its fins, its gill-rays, its scales, its air-bladder, and the shape of its head, and every species is placed by those characters alone. Yet it is a catalogue written with evident pleasure in the variety of the world, and it pauses often enough to tell the reader which fish are good to eat, which are salted and dried by Icelanders, which were prized by Roman epicures, and which are netted by the thousand in the coves of Long Island. The result is a work that is at once technical and humane—a scientific survey that keeps breaking into anecdote, history, and practical advice.
The arrangement is attributed to Cuvier, the great French comparative anatomist whose name stands on the title page, while the supplementary matter and the English dress of the volume belong to Griffith and Hamilton Smith. The book therefore represents a characteristic nineteenth-century collaboration: the continental system-builder’s framework carried into English by competent editors who added species, corrected names, and occasionally inserted observations of their own, such as the note on the egg-case of an Australian shark supplied by a naval captain. It is a work of reference rather than of argument, but it carries within it a whole philosophy of living things.
Context
The intellectual setting of the book is the age of classification. By the early nineteenth century, naturalists had accumulated an enormous mass of specimens from every ocean, and the pressing task was no longer discovery alone but order—deciding what a genus was, which characters were essential and which merely accidental, and how the teeming variety of fishes could be reduced to a manageable scheme. Linnaeus had provided the scaffolding, but his genera had grown unwieldy, and much of The Class Pisces consists of the patient work of subdivision: taking a Linnaean genus like Trigla or Sparus or Zeus and breaking it into smaller, more precisely defined groups such as Prionotes, Pagellus, Dentex, Cantharus, Boops, and Oblada. The book is thus a document of a science in the middle of a great house-cleaning.
The volume also reflects the practical world in which this science was embedded. Fish were food, and the treatise never forgets it. The sheep’s-head is praised in the words of an American naturalist who thought nothing could surpass a boiled sheep’s-head in a New Yorker’s opinion; the red mullet is remembered for the pleasure Roman diners took in watching its colours change as it died; the sea-wolf of northern seas is valued because Icelanders salt and dry its flesh, use its skin as shagreen, and its gall as soap. Natural history in this period was not a purely contemplative pursuit. It served fisheries, markets, and the law.
That last point is made explicit early in the book, in an anecdote about a New York trial over the duty payable on whale oil. The payment was resisted on the ground that the law spoke only of oils produced from fish, and a whale, strictly speaking, is not a fish. Learned professors gave evidence to that effect, but the jury, unimpressed by scientific distinctions, decided according to what they took to be the meaning rather than the letter of the statute. The book draws a moral from this: legislators who frame enactments touching scientific matters would do well to adopt the naturalist’s exact definitions, which cannot be evaded or misinterpreted. The anecdote is a small window onto the world the book inhabited—one in which the boundary between a whale and a fish was not merely an academic question but a matter of money, and in which the authority of the new zoology was still being negotiated in ordinary courts.
Structure of the Book
The work begins with general anatomy. Before a single genus is named, the reader is given the whole architecture of a fish: the definition of the class as oviparous vertebrata with a double circulation, breathing exclusively through water; the gills and their leaflets suspended on arches; the heart with its single auricle and ventricle; the arterial trunk beneath the spine that does the work of a left ventricle; the reduction of limbs to fins and the two kinds of fin-rays, spinous and soft. From there the survey moves through the skeleton—skull, jaws, teeth, hyoid and branchial apparatus, vertebrae, ribs, shoulder and pelvis—then through the muscles, the brain, and the cranial nerves, and finally through the organs of sense, one by one, with the eye receiving especially close attention and the ear shown to be little more than a labyrinth enclosed in the bones of the head.
Reproduction follows, and it is treated with the same thoroughness: the roe and the milt, the occasional hermaphrodite individual, the complicated organs of rays and sharks with their shelled egg-cases and true uteruses, the species that carry their spawn about with them, the vast numbers of eggs produced and the far greater numbers of young that perish. Only after this long anatomical and physiological foundation does the book turn to classification, and when it does, the first and largest order is the Acanthopterygii, the spiny-rayed fishes, which occupy the great bulk of the volume.
Within that order the arrangement is a descending series of families and genera, each defined by a small cluster of characters and each illustrated by its principal species. The mailed-cheeked fishes come early—the gurnards and their allies, with their enormous suborbital bones and their grumbling sounds when taken. Then the perches and their relatives, the mullets with their barbels, the sea-breams in all their subdivisions, the wrasse-like and parrot-like fishes, the blennies with their fringes and crests, the gobies with their united ventral fins, the sticklebacks with their spines and bony cuirasses, and onward into the great family of the Sciaenoides, the drums and croakers, whose complicated air-bladders seem somehow connected with the noises they make. The book proceeds by accumulation rather than by climax, each genus taking its place in a long chain of definition and example, and the reader is carried steadily through the order toward the families that follow.
Inside the Book
The Title Page and the Plan of the Work
The volume opens with its title page: The Class Pisces, arranged by Baron Cuvier, with supplementary additions by Edward Griffith and Lieut.-Col. Charles Hamilton Smith, printed in London for Whittaker and Co. in 1834. A list of plates follows, running from plate XXXII to LXII with their facing pages, alongside entries for the Australian Remora and the Dory.
The Fourth Class of Vertebrated Animals
The text proper begins by defining fish as oviparous vertebrata with a double circulation, breathing exclusively through water. Their gills are leaflets suspended on arches attached to the os hyoides, built of successive laminae covered with blood vessels; water swallowed by the fish escapes between the laminae and acts on the blood driven to the gills by a heart possessing only the right auricle and ventricle of warm-blooded animals. After respiration the blood passes into an arterial trunk beneath the spine that serves as a left ventricle, dispersing blood through the body before it returns by veins.
Fish structure is fitted to swimming as birds’ is to flight. Suspended in a fluid nearly their own weight, they need no wings; many species carry an air vessel under the spine that adjusts their specific gravity, helping them rise or sink. Progression comes from the tail striking water alternately right and left, with the gills discharging water backward probably assisting. The limbs are reduced—arm and leg bones extremely short or concealed—while the rays supporting membranaceous fins stand in for fingers and toes: pectorals for the anterior extremities, ventrals for the posterior, and dorsal, anal, and caudal fins along the back, beneath the tail, and at its end. Rays are either spinous, made of a single bony piece, or soft and articulated, divided into branches at the tip.
Limbs vary as among reptiles: generally four, sometimes two, sometimes none. The scapula may hang in flesh, attach to the spine, or more commonly join the cranium; the pelvis seldom adheres to the spine and often lies before the abdomen. Vertebrae are united by concave surfaces filled with cartilage and communicate by a canal through the axis, most bearing long spinous processes. The head varies more in form than in any other class, though built from the same bones as other oviparous animals. Fish have tubercles at the base of the olfactory nerves; nostrils are simple fossae lined with a plaited membrane; the eye has a flat cornea and a nearly globular, very hard crystalline; the ear is a sac representing the vestibule, holding small stony masses and three semicircular canals, with neither eustachian tube nor tympanal bones. Taste must be dull, since the tongue is largely bony; most fish have scales, and all lack an organ for holding, though fleshy tendrils may partly supply touch.
The intermaxillary forms the upper jaw’s edge, with the maxillary behind it, and a palatine arch constitutes an interior jaw as among birds and snakes. Teeth appear on intermaxillaries, maxillaries, lower jaw, vomer, palatines, tongue, gill arches, and pharyngeal bones, in countless combinations and forms. The os hyoides carries the rays of the branchial membrane, and a lid of three bony pieces closes the gill opening. Stomach and intestines vary as in other classes; the pancreas is represented by caeca round the pylorus; kidneys lie along the spine, and the bladder opens behind the anus and generative parts, contrary to mammalia. Testicles are two enormous glands, ovaries two sacs holding ova. Some fish copulate and are viviparous; selacians alone have long oviducts, sometimes leading to a true matrix. Most fish do not couple: the female deposits spawn and the male fecundates it with milt.
Whale Oil, and the Nature of Fish Life
A few years earlier a New York trial turned on duty owed for whale oil, resisted on the ground that the law spoke only of oils produced from fish, and a whale was not a fish. Learned naturalists and professors testified that whales were not fish, but the jury, unpersuaded by scientific distinctions, gave a verdict according to what they took to be the law’s meaning rather than its letter. The passage suggests legislators might profit from naturalists’ exact phraseology, which cannot be evaded or misinterpreted—the definition of fish just given being a proof in point—and notes that the Church of Rome regards the coot as fish, asking why seal oil should not legally pass as the produce of fish.
From the definition, the whole nature of fish can be deduced. Being vertebrated, they possess an internal skeleton, brain and spinal marrow enclosed in the vertebral column, muscles outside the bones, four extremities only, and the organs of the first four senses in the head’s cavities. As aquatic beings in a heavier, more obstructing liquid than air, their locomotive organs serve progression: the tail holds the principal muscular power, members are short but expansible and membraned, and the teguments are smooth or scaly, free of hair or feathers.
Breathing only through water, restoring their blood by oxygen suspended in it, their blood is cold and their vitality, senses, and movements weaker than those of mammalia and birds. Their brain is proportionably much smaller, and of all vertebrated animals they show the least sensibility. Lacking elastic air, they are nearly destitute of voice and of the sensations that faculty awakens. Their immoveable eyes, fixed osseous faces, and members moving only as wholes give no play to physiognomy. Their ears, enclosed in the cranium and lacking conch and cochlea, can scarcely hear the loudest sounds; condemned to the empire of silence, they have small occasion for hearing. Their large eyes partly offset the scantiness of light, but the iris can neither dilate nor contract, no tear moistens and no eyelid shelters the surface.
Compelled to live by chasing prey, with no means of securing it but deglutition, delicate taste would be useless; the tongue, almost immoveable and often osseous or beset with dental plates, is blunted. Smell cannot operate as in air-breathing animals. Feeling, almost obliterated by scales and by the inflexibility of the rays, is confined to the tips of the lips, sometimes themselves bony. Hence nature must appear indistinctly to them, their pleasures little varied, their apprehensions chiefly the pain of wounds. Except in the season of love, hunger is the want that drives all their activity; when not reproducing, their predominant passion to devour is almost their sole occupation. Their whole conformation serves pursuit or escape, determining their choice of residence and the differences of form among them—the angling filaments of lophii, the extensile jaws of epibuli and corici, and the electrical shocks of torpedos and gymnoti have no other object. Fish are but slightly affected by temperature, their bodies assuming that of the surrounding fluid, so the seasons are not the exclusive regulators of their migrations and propagation as with mammifera.
Bones, Articulations, and Composition
Fish skeletons are bony, fibro-cartilaginous, or truly cartilaginous. The truly cartilaginous are the chondropterygians, distinguished by their whole framework, by branchiae whose external border fastens to the skin and lets water escape through narrow multiplied openings, and by other marked details.
The Reproductive Anatomy of Fishes
The passage opens with a discussion of fish reproductive anatomy. In some fishes the roe is not contained in bags but in a collection of leaflets; no canal is visible, so the spawn can escape only by dropping into the abdomen and passing out through one of the two openings at the side of the vent. This is believed of the lamprey and conjectured for eels; even trout is asserted to be in the same condition, since the ovaries are closed on the side of the abdominal cavity and what might be taken for the oviduct is reduced to a simple ligament. The number of roe eggs in prolific species is sometimes prodigious, amounting in several to hundreds of thousands.
Occasionally individual fishes are found with an ovary on one side and a milt or testiculus on the other, making them true hermaphrodites. Certain species seem naturally to unite both sexes: Cavolini asserts this for a serranus, and Sir Everard Home for both eels and lampreys.
Rays and squali have more complicated organs. The testicles of rays, placed upon the stomach toward the summit of the abdomen, are composed of harder, rounder lobes and a softer part resembling the milt of ordinary fishes; in squali they form large cylinders coiled in a vermiform manner and internally divided into an infinity of small vessels. From their summits arise two epididymi, each composed of many folds of a single vas deferens, becoming smaller and less tortuous near the vent; after swelling into a seminal vesicle, it opens with the other side into a conical prominence on the superior side of the rectum near the vent. Females have two ovaries where the yolks grow as in poultry; those that escape are received by funnels of the two oviducts opening above the liver near the diaphragm. These oviducts are membranous at first and traverse a kidney-shaped gland that seems to secrete the horny substance of the shell; after passing through, the roe descends the channel into a bag above the rectum constituting a real uterus, opening by a large orifice at the extremity of the rectum. Sturgeons show some modification. The egg spawn of rays is fibrous, resembling horn, square, flattened, with angles prolonged into points. In sharks the surface is often yellow and transparent, oblong, with angles terminating in long coils of horny cords, which the Baron considers secreted in the lateral furrows of the oviduct traversing the gland. The spawn of chimaeras is wrapped in a strong flat shell of horny substance, oval and hairy; that of callorinchus Australis resembles a broad leaf of sea-weed, within whose coats the fish, already perfect in form, is discovered suspended in fluid.
In viviparous squali, whose embryos develop in the oviducts or uterus, such as true sharks, the foetus has only a membranous wrapper still showing the tortuous cords found about the shell of others.
Some species carry their egg-spawn after extrusion, others until the fry is brought forth. Syngnathus possesses behind the vent, in the basis of the tail, a groove closed by two scaly pieces like shutters, wherein the roes remain in order until hatched; this caused Aristotle to assert that this fish splits for spawning. Aspredi carry their roes attached to the skin of the belly. Most fishes produce roes in the water, agglutinated by mucilage attaching them to stones and aquatic plants, sometimes in bunches, cords, or net-work; the roes are then transparent globules with the yolk visible. They are fecundated by the milt of males passing over them, at which period the males show greatest activity; many then ascend rivers, some live in pairs, others become gregarious and migratory. The germ appears earlier or later according to temperature, and growth is generally slow; the young fry usually opens a passage with its tail through the covering membrane. In osseous viviparous species, such as siluri, anableps, and certain blennies, the roe swells in the ovarium sufficiently for the foetus to grow within.
All egg roes contain, beside the foetus, a vitellus communicating by a pedicle with the foetus’s intestine, and an external membrane similar to that of birds’ eggs. No amnios has been observed; the internal tunic involving both foetus and vitellus can scarcely be admitted as such. The principal distinction between the roe of fish, the spawn of batrachi, and the eggs of animals that breathe by lungs when hatched is that they are totally devoid of the allantoid and umbilical vessels, which are at no time discernible; hence there is no placenta, yet the vitellus of the foetus of sharks appeared to the Baron much contracted and adhering to the uterus nearly as firmly as a placenta, the cord being much ramified with vascular appendices like coarse hair.
Once brought into external life, the fish is left to its own powers of subsisting. The far greater number perish, devoured by larger fish, aquatic birds, and reptiles; survivors increase in size with greater or less rapidity according to species. In some this growth continues nearly the whole of their lives, and others have considerable duration; carps, for example, are said to attain the age of more than a century.
The First Order of Fish: Acanthopterygii
After this rapid sketch of the class’s organization, the text proceeds to the Baron’s distribution of the first order. They form the first and much the most numerous division of common fish. They are known by the spines representing the first rays of the dorsal fin, or which alone sustain their anterior fin of the back.
The Family of Mullets
The passage continues a systematic survey of the order Acanthopterygii, treating several fish families and genera. It opens with a group of small fish resembling the sphyrsense, whose second dorsal fin is so small and brittle it was thought to be adipose. The genus Mullus is then described as nearly allied to the percoides by many external and anatomical details, yet forming a separate family due to remarkable peculiarities: two widely separated dorsal fins; the whole body and opercula covered with large scales that easily fall off; a preoperculum without denticulations; a little-cleft mouth feebly armed with teeth; and, most distinctively, two long barbels attached to the symphysis of the lower jaw. It is divided into two subgenera. Mullus proper has only three gill rays, an operculum without spines, an upper jaw without teeth, a vomer with two large plates of closely set small teeth, and no air-bladder; all species are European. M. barbatus has a nearly vertical profile and bright red colour, is celebrated for flavour, and for the pleasure Romans took in contemplating its colour changes in dying; it is more known in the Mediterranean. M. surmuletus is larger, with a less vertical profile, striped longitudinally with yellow, and more common in the ocean. Upeneus has teeth in both jaws, frequently none on the palate, a small opercular spine, four gill rays, and an air-vessel; all species come from warm-climate seas.
Fish with Armed Cheeks
The second family of the acanthopterygii, “Fish with armed cheeks,” contains numerous fish whose bristled, armour-covered heads give a peculiar physiognomy and caused them to be classed in special genera, though they share much with the perch.
The Blennies and Their Kin
Cuvier continues his survey of the genus Blennius, cataloguing species distinguished by the structure of the dorsal fin, by filaments or fringed appendages above the eyes, and by markings such as a black spot between fin rays. He separates out a group lacking prominent brow tufts but bearing a membranous, reddening prominence on the crown during the nuptial season, and another—Artedi’s Pholis—with neither tuft nor crest, common on the coast of France. From the true blennies he then carves several subgenera: Myxodes, with its elongated head and pointed muzzle; Salarias, whose laterally compressed, hooked, astonishingly numerous teeth move like harpsichord keys in the living fish, and whose intestines coil spirally; and Clinus, with short pointed teeth in several rows and a wider stomach. Cirrhibarba resembles a clinus but bears large tentacles on muzzle and lower jaw, while Murænoides has smaller ventrals, a tiny head, and an elongated body.
Opistognathus, Zoarcus, and the Sea-Wolf
The genus Opistognathus is marked by enormous maxillaries drawn out into a long flat moustache and rasp-like teeth, with O. Sonnerati the sole known species, brought from the Indian Ocean. Zoarcus lacks a spinal ray but has an anal tubercle and intestines without caeca; Z. viviparus is viviparous in European seas, and Z. labrosus a larger American form. The Anarrhichas, so blenny-like that Cuvier would gladly call them blennies without ventrals, are smooth, slimy, and ferocious, armed with powerful bony tubercles and small enamelled teeth. The sea-wolf, A. lupus, inhabits northern seas and is precious to Icelanders, who salt and dry its flesh, use its skin as shagreen, and its gall as soap.
The Gobies and Their Relatives
The gobies, or sea-gudgeons, are recognized by their united thoracic ventrals forming a single hollow disk; they can live out of water, and the males bear a post-anal appendage. They favour clayey bottoms, dig canals for winter, and in spring prepare nests among fucus which the male defends. Cuvier lists numerous species, freshwater and foreign alike. Gobioides differs only in having a single dorsal fin; Tænioides is more elongated still, with hooked teeth and an almost hidden eye, living in the mud of East Indian ponds. Periophthalmus, with scaly head and pectorals, can survive out of water even longer, and is seen in the Moluccas creeping and leaping over mud to catch shrimps. Eleotris has flexible spines and entirely distinct ventrals, inhabiting fresh water and mud, such as E. dormitatrix of the Antillean marshes.
Xyrichthys, Chromis, and Cychla
The xyrichthys resemble a labrus but are far more compressed, the front descending in a trenchant, almost vertical line; their scales are large, the lateral line interrupted, and the pharynx paved with hemispherical teeth. Naturalists had long placed them with the coryphaenae, from which they differ greatly, internally and externally. Cuvier notes X. novacula, the razor-fish, esteemed as food, and corrects various confusions among named species. Chromis combines the lips and general appearance of a labrus with the pharynx and jaw teeth of a scarus; C. vulgaris is the common coracinus of the ancients, taken by thousands in the Mediterranean, while C. niloticus is the prized white coracinus of the Nile. Cychla differs from chromis in its small crowded teeth and more elongated body, and Cuvier strikes out many of Bloch’s species, reassigning them to other genera—observing that Bloch was as unfortunate in constructing Cychla as he had been with Grammistes. Plesiops and Malacanthus follow, the latter combining labrus-like teeth with scarus-like pharyngeals, its Antillean species known as the Vive.
Sticklebacks and the Centriscus
Sticklebacks appear in nearly every stream or pond, sometimes swarming in certain seasons; their mailed cheek is smooth and hidden beneath the skin, matching the structure seen in trigla. Their French, English, and other European names all derive from the spines arming the back and replacing the ventral fins, while Gasterosteus expresses the bony cuirass of the belly. The naked-tailed and armed-tailed species are the largest, and what naturalists treated as a single species may comprise several. They occur wherever there is stream, marsh, or pool, and Pennant reports them ascending the river Welland at Spalding in surprising quantities every seven or eight years. Their multiplication is astonishing given their few, large eggs; they fear little from other fishes thanks to their sharp spines, though they suffer from a parasitic binoculus and from the tapeworm bothriocephalus solidus. They survive long out of water, leap vertically over a foot, and are excessively voracious—one was seen to devour seventy-four newborn fish in five hours. As food they are little esteemed. Theophrastus’s centriscus, a little fish of Heraclea absurdly numbered among creatures springing from corruption, was thought by Klein to be the stickleback, and he accordingly gave the genus that name. Cuvier notes France has two sorts of three-rayed sticklebacks, the smaller pungitius scarcely weighing half an ounce, spread through Europe and even into salt water. The oreosoma, a small fish bristling with thick cones like sugar-loaves, seems more a monstrous product of morbid imagination than reality; brought from the Atlantic by Peron’s indefatigable attention, its specimen does not exceed sixteen lines.
The Sciaenoides and the Sheep’s-Head
The great family of sciaenoides shares nearly all the external characters of the percoides, and the mailed-cheek family establishes a passage between them. They resemble percoides internally as well, but show more varied and complicated natatory bladders, and emit more marked noises—making it hard to believe the organ’s disposition is unrelated to the sound. They are scarcely less numerous than the percoides, with similar habits and utilities; almost all are good eating, and some reach sizes equal or superior to the largest percoides. The sheep’s-head, unknown to Linnaeus and ignored by Gmelin, is described in Dr. Mitchill’s memoir on New York fishes, which praises its flesh as yielding only to trout and salmon. It is an important fishery on the New York coast, approaching Long Island from June to mid-September and taken in troops by the hundred at a single cast, packed in ice and hurried to market by night.
The Daurade and Its Ancient Fame
The chrysophris species are numerous and extend through all seas, the Mediterranean producing two not yet distinguished from each other.
The Tunny and Its Ancient Fisheries
The supplement turns to the Acanthopterygii, beginning with the tunny and its kin. The genus Thynnus gathers the thunninae, the orcynus or germon, and the striped-bellied bonitoes, distinguished from the mackerel by the arrangement of the thoracic scales—larger, duller, and forming a corslet that divides behind into points. The common tunny, Scomber thynnus, is counted among the largest sea-fishes and among the most beautiful, useful, and agreeable. Aristotle records an old individual of fifteen talents, some twelve hundred pounds, measuring two cubits and a palm from point to point of the caudal fin—a reading corrected by Gaza and followed by Pliny, though most manuscripts say five cubits, which would give a fish of twenty or twenty-two feet. In Sardinia, tunnies under a hundred pounds are called scampirro, a diminutive of scomber; those from a hundred to three hundred pounds are reckoned half-tunny. Specimens of a thousand pounds are not rare, and Cetti claims some reach eighteen hundred, adding that the largest are always males—the reverse of most other fishes.
The fishery is of the highest antiquity. Verses once attributed to Hesiod describing the trade are shown by Athenaeus to belong to a much later poet. The greatest fisheries lay at the two extremities of the Mediterranean, where the sea contracts and migratory fish are forced into closer contact. In the East, the Black Sea fed the trade through its many rivers: the fish repaired thither in spring to spawn, remained through summer, and were taken in rich captures on their passage to the Bosphorus. Strabo places their reproduction in the Palus Moeotis; following the coast of Asia Minor, the first were taken small at Trebizond and Pharnacia, growing large enough for salting by the time they reached Sinope, a town built on an isthmus that drew immense profits. Byzantium was especially enriched. Shoals entering the Bosphorus near Chalcedon met a white rock that terrified them, turning them toward Byzantium and into the gulf that is now the port of Constantinople, so all advantage fell to the Byzantians while the Chalcedonians reaped little. Cuvier says this abundance gave the gulf the name Golden Horn, and the oracle of Apollo called Chalcedon the City of the Blind for failing to recognize its inferiority. Gibbon, more plausibly, traces the name to the curve resembling an ox’s horn, the epithet golden expressing the riches wafted from distant countries; he adds that the river Lycus pours perpetual fresh water into the harbour, cleansing the bottom and inviting periodical shoals. The Propontis has ever been renowned for an inexhaustible store of exquisite fish, taken in their seasons almost without labour—among them the Pelamides, the young tunnies of Chalcedon, which Aulus Gellius calls the most esteemed. Gyllius describes them with astonishment: they abound more than at Marseilles, Venice, and Tarentum; twenty vessels might be filled with a single cast of the net; they may be taken by hand, killed with stones, caught by women lowering baskets from windows, and provision all Greece and much of Europe and Asia without bait. Dupper and, recently, von Hammer confirm this, the latter noting that the Bosphorus swarms with fish—hence the dolphin and two fishes on the medals of Byzantium. Cuvier laments that of so many Europeans who pass part of their lives in that capital, none should precisely determine these numerous species and the periods and directions of their passages.
In the West the fishery was still more ancient. The Phoenicians established it early on the coasts of Spain, prosecuting it within and beyond the columns of Hercules, and the tunny appears on Phoenician medals of Cadiz and Carteia. The salted fish of Spain and Sardinia were reckoned in Roman times more tender and agreeable than those of Byzantium and sold at a higher price, known generally as saltamentum Sardicum. Their savoury quality was attributed to acorns falling from a small oak common on those coasts—people believing the oaks grew at the bottom of the sea, though these are probably fucus. Tunnies that moved farther toward the straits of Gibraltar grew thinner, no longer finding this aliment.
The Labyrinthiform Pharyngeals and the Climbing Fish
The text then introduces the family of Labyrinthiform Pharyngeals, remarkable for a structure dividing part of the upper pharyngeal bones into leaves, producing cavities fit for retaining water, compared to the net-work of the camel’s paunch. This apparatus is shut under gibbous opercula closing against the body, so the contained water does not easily evaporate but flows over the gills, hindering them from drying. Accordingly, all authenticated fishes of this family can leave rivers and ponds and travel considerable distances by creeping through grass or on the ground. Theophrastus had already described small Indian fishes that come forth from rivers and return, resembling the mugiles of the Greeks.
The first subgenus is Anabas, named by Cuvier from the Greek for “to ascend.” Two Danish observers at Tranquebar witnessed a climbing habit in the common species. Lieutenant Daldorf, in the Linnaean Transactions of 1797, affirms that in November 1791 he took one such fish in the cleft of the bark of a palm-tree, borassus flabelliformis, near a pond—five feet above the water, ascending by fastening to the bark with the spines of its opercula, bending its tail, hooking by the spines of its anal, then raising and fixing itself afresh. John tells a similar story: the fish remains in muddy pond bottoms, creeps on dry ground by inflexion of its body, and climbs palm-trees by its serrated opercula and fin-spines. Other observers are silent: Keinwardt, who often took the anabas at Java, never heard the habit attributed; Leschenault, sending specimens from Pondicherry, says only that they inhabit rivers and ponds; Hamilton Buchanan denies the fact as contrary to the whole order of nature, supposing Daldorf’s observation accidental. All agree, however, that the fish can live out of water for a long time, creeping on earth for hours; fishermen keep it five or six days in a dry vessel, and it is brought alive to the markets of Calcutta from marshes more than a hundred and fifty miles distant. People believe such fish fallen from heaven, an opinion also held of the ophicephali, and jugglers of India keep them in vessels to amuse the populace.
Little is known of Polyacanthus, Macropodus, and Helostoma, but similarity of conformation suggests the same habits and fresh-water residence. Buchanan reports several Bengal fishes of the same family, inhabiting ponds, marshes, and dykes watered by the Ganges, agreeable to taste but too small to be important food, able to live on dry land; in Bengal all are comprehended under the name Colisa, which Cuvier uses to designate a genus. The most celebrated approximating fish is the gourami, or Osphromenus of Commerson, who named it from the Greek for “I smell,”
The Carp: Fecundity, Domestication, and Monstrous Forms
Carps feed on insect larvae, worms, small testacea, grains, roots, and tender plant shoots, and they will dart from the water to seize hovering or fallen insects. Their jaws make a peculiar noise when eating, audible at a distance, and though they can endure long fasts, they eat so gluttonously when food is abundant as to bring on fatal indigestions. In winter they bury themselves in mud and pass months without eating, assembled in great numbers side by side; in spring those in rivers move to more tranquil, plant-covered waters. Many males often follow one female, and when a barrier opposes them they sometimes raise themselves six feet out of the water, bringing head and tail together and suddenly releasing this circular spring to cross it.
Their fecundity is astonishing. The ancient Greeks consecrated them to Venus, and from the third year they can reproduce, with egg numbers increasing with age: Bloch found 237,000 eggs in a one-pound female, Petit 342,144 in a pound-and-a-half female, Bloch again 621,600 in a nine-pound female, and Schneider 700,000 in a ten-pound female whose ovaria alone weighed three pounds ten ounces. Much spawn is devoured by other fish, but at three years their only feared enemies are larger pikes and otters. Of all fresh-water fish the carp seems to grow fastest, weighing about three pounds at six years and six to eight at ten. Man esteems its flesh and rears it domestically, placing carps in ponds and castrating both males and females to fatten them and give a more delicate flavour, as is done with oxen, sheep, capons, and pullets. Samuel Full reduced this to profitable practice, opening the ovary, removing the eggs, inserting a piece of old hat, and uniting the wound by suture; he communicated the process to Hans Sloane, and it was frequently repeated with success.
Carps can be kept alive out of water a considerable time, carried packed in plants, moistened linen, or snow with a piece of bread steeped in brandy in their mouth, though transport in boats allowing water inside is safer. In Paris there are constant magazines in the middle of the river, often filled from more than one hundred leagues away, and in Holland a peculiar process preserves and fattens carp alive by suspending them in nets of humid moss and feeding them bread steeped in milk. The ancients did not highly esteem carp flesh, but today it is highly prized, especially in France, and a caviar is prepared from carp eggs as from sturgeon eggs. Carp bile is used by painters as a green colour. Monstrous carp are frequent, including one in the Museum of Paris whose mouth has no external orifice other than the gill holes, and Bloch opened carps that were hermaphrodites, having eggs in one ovary and milt in the other. In Germany, mules of the carp and characinus are frequently met, recognized by smaller scales and a thicker, shorter head without barbels.
The Goldfish and Its Spread from China
The goldfish appears originally native to a lake near Mount Tsienking, in the Chinese province of The-kiang, about the thirtieth degree of latitude. It is now spread through other Chinese provinces, Japan, all Europe, and America, owing to its brilliant and varied colours, which cause it to be kept domestically. Like other animals man has subjected, it presents almost numberless varieties of hue and form; Chinese carp are generally black in their first years, silvery points then announcing the development of their magnificent dress, which occasionally disappears in old age. In a spacious pond they may reach eleven to fifteen inches. They have been bred in England from the year 1011, and the first seen in France were brought for Madame de Pompadour.
The Herring, Shad, and Pilchard
No precise knowledge exists of how long herring spawn takes to disclose the young, nor of the time needed to reach maximum size; the usual length is about ten inches. It multiplies astonishingly, with 68,606 eggs counted in a single female, so herrings do not diminish despite many causes of destruction. Their vast shoals cover immense sea surfaces yet proceed in perfect order, with the largest and boldest leading. Thousands are taken by cetacea, squali, other large fishes, and sea-birds; many perish in bays where they crowd and suffocate against shallows. In a small Norwegian creek more than twenty million herrings have come from a single fishery, and Bloch calculated that inhabitants near Gothemburg take annually more than seven hundred million, yet this is nothing compared to catches by fishermen of Holstein, Mecklenburg, Pomerania, France, Ireland, Scotland, England, the United States, Kamtschatka, and above all Holland. Greek and Roman writings show no acquaintance with the herring, so it is not the halec or halex of Pliny; it appears as food in France as far back as the thirteenth century.
The shad is much larger than the herring, attaining nearly three feet but seldom weighing more than four pounds, inhabiting the North Atlantic, Mediterranean, and Caspian Seas. In spring it ascends great rivers in numerous troops, sometimes reaching the sources, and when escaping it agitates violently and makes noise audible at a distance. It is said to be terrified by thunder, yet Mediterranean fishermen believe it is fond of music and employ musical instruments, attaching small bells to boats—a prejudice that probably saves numbers of shads. The Loire is the French river where they most abound, and Ausonius says that in his time the shad was regarded by the Bordelais as food fit only for the lowest people, a remarkable example of changed taste since today it is served on the best tables. Russians imagine it has deleterious qualities, throwing shads out of nets or selling them cheaply to Tartars, while the Arabs dry them in the air and eat them with dates.
The pilchard is about the size of the herring, caught particularly on the coast of Cornwall, arriving in large troops toward the end of July, disappearing in autumn, and reappearing at the beginning of January. Severe cold sometimes retards their return, and storms turn them from their course. Their arrival is indicated at a distance by the concourse of sea-birds, by the phosphoric light emitted by these fishes, and by the odour exhaled from their milt. They form a useful and important article of commerce, their flesh being fat and well-flavoured and yielding considerable oil.
The Third Order: Malacopterygii Subbrachiati and the Cod Family
The third order of fishes, Malacopterygii Subbrachiati, is characterized by ventrals attached under the pectorals, with the pelvis immediately suspended to the shoulder bones, and contains almost as many families as genera. The first family, Gadoides, is composed almost entirely of the great genus Gadus, recognized by ventrals attached under the throat and sharpened to a point. Gadus resembles the English name cod; its body is moderately elongated and little compressed, covered with soft scales, with a well-proportioned head without scales and all fins soft. The jaws and front of the vomer are armed with pointed, irregular teeth in several ranks, forming a currycomb or rasp, and the gills are large with seven rays.
The Plectognathi: Tetrodons, Sun-Fish, and Triodon
Cuvier turns to fishes whose jaws are divided by a suture so that they appear as four teeth, two above and two below, their skin set with small, inconspicuous spines, several species reputed venomous. The oldest known is the Nile fish, the Tetraodon lineatus, striped brown and whitish, which the inundations cast ashore in numbers to serve as playthings for children. Some tetrodons have laterally compressed bodies and slightly trenchant backs, less liable to inflation—one of them electrical. A footnote sets out a whole classification by smooth and rough surfaces and head shape, and corrects earlier errors: what Lacepède took for a hump is merely the pectoral of the far side, and the supposed Spheroïde tubercule is the same fish drawn face-on by Plumier.
The Orthagoriscus, the sun-fish and moon-fish, share the undivided jaws of the diodons but have compressed, spineless bodies that cannot inflate, and a tail so short and vertically high that their figure is extraordinary; dorsal and anal fins merge into the caudal, there is no swimming bladder, the stomach is small, and a thick gelatinous stratum lies beneath the skin. One of our seas can produce a specimen over four feet long and three hundred pounds, with rough silvery skin. A footnote suppresses two genera—Ovoïde and Ovum—as mutilated tetrodons that had lost their fins, and adds an oblong Cape species with skin divided into small angular compartments, and a third, spiny oceanic form.
A distinct genus, Triodon, is then established: its upper jaw is divided as in the tetrodon, its lower simple as in the diodon, and an enormous dewlap, nearly as long as the body and twice as high, is supported in front by a large bone representing the pelvis, bringing it near certain balistes. Its fins resemble the diodon’s, its body is rough like the tetrodon’s, and the dewlap bristles with small oblique crests. One species is known, from the Indian Ocean, discovered by Reinwardt.
The Sclerodermes: Balistes and Monacanthus
The second family of plectognaths, the Sclerodermes, is marked by a conical or pyramidal muzzle prolonged from the eyes and ending in a small mouth with few distinct teeth in each jaw, skin generally rough or hard-scaled, and a large, robust oval swimming bladder. The Balistes have compressed bodies, eight teeth in a single range in each jaw, and skin scaly or grained rather than truly bony; a first dorsal of one or several prickles articulates on a special bone attached to the cranium, with a furrow to fold them away, while a soft second dorsal opposes the anal. Though they have no ventrals, a true pelvic bone hangs from the shoulder. They swarm in the torrid zone near rocks, brilliant as chaetodons; their flesh is little esteemed and said to turn dangerous when they feed on coral polypi, though the author found only fucus in those he opened. A footnote derives the name from the Italian Pesce balestra, from the cross-bow-like motion of the great dorsal spine.
Balistes proper clothe the whole body in large, very hard rhomboidal scales that look like compartments; the first dorsal carries three prickles, the first largest, the third tiny and set farther back. The pelvic extremity is always salient and prickly, with spines buried in the skin behind it. Some species arm the tail with ranges of forward-curved spines—two or three ranges, four or five, six or seven, even twelve or fifteen—while others, like the Mediterranean Balistes capriscus, have no such armature. A footnote notes that if Tilesius’s Balistapus truly lacks the pelvis, it should form a subgenus at the end of the balistes proper. The Monacanthus follow, with very small scales crowded with stiff excrescences and a projecting spiny pelvis, but only a single large dentated spine to the first dorsal.
The Chondropterygii: Sharks and Their Kind
The survey passes to the cartilaginous fishes, opening with a list of Squalus species and their synonyms—the Roussette of Gunner, the Sq. Africanus or galonne of Broussonet—with notes correcting Gmelin’s gratuitous additions and identifying the pretended Sq. canicula as a distinct foreign species. The Carcharias, a numerous and celebrated tribe, have trenchant pointed teeth often dentated on their edges, the first dorsal far before the ventrals, no air-holes, and a depressed muzzle with nostrils beneath its middle. The common white shark, the Requin, reaches twenty-five feet, its upper teeth nearly isosceles triangles with jagged edges, its lower with a narrow point on a broader base—a terrible weapon and the terror of navigators. Also caught on our coasts are the fox shark or thrasher, with a tail lobe as long as its whole body, and the blue shark with long pointed pectorals.
Lamna differ only in their pyramidal muzzle and gill-holes placed entirely before the pectorals; Galeus resemble sharks but possess air-holes; Mustelus add air-holes and small rounded teeth; Notidanus lack the first dorsal and are remarkable for six or even seven wide branchial apertures. Selache, joining shark form and air-holes to enormous gill openings and small conical teeth, includes the basking shark, which exceeds thirty feet yet has nothing of the shark’s ferocity. Cestracion have a spine before each dorsal and broad rhomboidal teeth toward the jaw angles, known from New Holland. Among the species without an anal but with air-holes, Spinax is distinguished by a strong spine before each dorsal—the Sq. Acanthias being one of the commonest in our markets—while Centrina joins spines and air-holes to a second dorsal set over the ventrals and a short tail.
The Supplement: Spatularia and the Sharks’ Generation
The supplement opens with Shaw’s Spatularia, whose habits are unknown and whose odd form words cannot convey, so a figure is inserted; it rarely exceeds a foot and is uniformly greyish. The chondropterygians with fixed gills begin with the great Linnaean genus Squalus, now divided by air-holes, the post-anal fin, and the disposition of head, muzzle, and teeth. Their generation is ovoviviparous: the eggs hatch in the mother’s oviduct, though they may be expelled before the embryo quits them without destroying the young. These eggs, the sailors’ purses, are tough coriaceous parallelograms like little pillows, with a long curling filament at each angle; each pair seems to require separate fecundation, only two being produced at a parturition. The foetus lies coiled, attached by a thread-like membrane to a white oval substance, and the tendrils catch at sea-weed to hold the young until it departs.
Main Arguments
The central claim of the book is that a fish is not simply an animal that lives in water but a precise anatomical proposition. The definition offered at the outset—oviparous vertebrata with a double circulation, respiring exclusively through water by means of gills—is presented as a model of what a definition should be: exact, exclusive, and incapable of being stretched. Everything that follows is, in a sense, an elaboration of that proposition. Because fishes are vertebrated, they must have an internal skeleton, a brain and spinal marrow enclosed in the vertebral column, muscles outside the bones, four extremities at most, and the organs of sense lodged in the cavities of the head. Because they live suspended in a fluid nearly as heavy as themselves, they need no wings; their limbs shrink to fins, their tails take on the principal muscular power, and their skins become smooth or scaly, free of hair and feathers.
From the same premises the book derives a second argument, about the mental and sensory life of fishes. Breathing through water alone, their blood is cold, and their vitality, the energy of their senses, and the force of their movements are consequently less than in mammals and birds. Their brains are proportionately much smaller. Their eyes are fixed and cannot change direction or accommodate to distance; the pupil never alters under any degree of light; no tear moistens the surface and no eyelid shelters it. Their ears, enclosed in bone and lacking both external conch and internal cochlea, can scarcely hear the loudest sounds. Their tongues are largely bony and their sense of touch is confined to the tips of their lips. The conclusion drawn is that of all vertebrated animals, fishes show the least signs of sensibility—that nature must appear indistinctly around them, that their pleasures can be but little varied, and that hunger, except in the season of love, is almost their sole occupation.
A third argument concerns the purpose of fish form. The book insists that the entire conformation of these animals is organised around pursuit and escape. To chase a prey or avoid a destroyer is the constant business of their lives; it determines where they live, explains the differences of shape among them, and accounts for the small portions of instinct and artifice nature has granted to some species. The angling filaments of the fishing-frogs, the extensile jaws of certain predatory genera, the electric shocks of the torpedo and the gymnotus—all are read as instruments of the same unending chase. Even the sense of taste is explained away: since fish have no means of securing prey except by swallowing it whole, delicate sensations of taste would have been useless even if nature had bestowed them.
Finally, the book argues implicitly for the power of comparative anatomy as a classifying instrument. Again and again, a genus is separated from its neighbours not by colour or habit but by a single structural fact: the union of the ventral fins into a disc, the immovable suture between suborbital and preoperculum, the absence of vomerine teeth, the presence of a second lateral stria, the form of the air-bladder. The whole vast catalogue rests on the conviction that internal structure is the surest guide to true relationship, and that external resemblance, however striking, may be deceptive.
Key Concepts
Several organising ideas recur throughout the work and give it its intellectual shape. The first is the distinction between spinous and soft fin-rays. The rays that support the fins are of two sorts: single bony pieces, generally hard and pointed, sometimes flexible and elastic, and soft, articulated, or branched rays made of many small joints and usually divided at the tip. This distinction is not a minor technicality; it underlies the very name of the first and largest order, the Acanthopterygii, or spiny-rayed fishes, and it governs the placement of genus after genus.
The second concept is the air-bladder, or natatory bladder—a vessel beneath the spine that changes the fish’s specific gravity by compression or dilatation and assists it in rising or descending. The book returns to this organ repeatedly, noting its presence or absence as a diagnostic character, remarking on its complicated forms in the Sciaenoides, and puzzling over the apparent connection between its structure and the noises those fishes emit. In one remarkable instance, the skeleton of a genus called Kurtus is described as having dilated, convex ribs forming contact rings that enclose a conical empty space extending beneath the tail in a long thin tube which contains the bladder—an arrangement unlike anything else in the class.
The third concept is the division of fishes into osseous, fibro-cartilaginous, and truly cartilaginous forms. The truly cartilaginous fishes, the chondropterygians, are set apart by their whole framework, by gills whose external border is fastened to the skin and allows water to escape through narrow multiplied openings, and by other marked details. They lack real bones; their hard parts are internally only cartilage, sometimes covered with small opaque calcareous granules, as in rays and sharks. The book is careful to insist that fibro-cartilaginous genera were wrongly associated with them, since in those fishes the calcareous matter is disposed in fibres and layers as in hard-boned fishes, only less abundantly.
A fourth concept is the peculiar character of fish bone itself. Neither osseous nor cartilaginous fishes have epiphyses on their bones or a medullary canal within them. Some bones are so homogeneous and solid as to show no pores or fibres and appear vitreous; in others, like the dory, the internal part remains cartilaginous while the surface is completely ossified; and in some, like the pike, certain bones of the head remain permanently in a state of cartilage while the rest of the skeleton hardens. The chemical analysis given—an organic base penetrated by phosphate of lime and magnesia with oxide of iron, together with some sub-carbonate of lime, and an oil principally composed of oleine—is offered as the material explanation of these differences.
A fifth concept, and one of the most distinctive in the book, is the apparatus found only in osseous fishes: a variously twisted band forming an incomplete ring around the optic nerve, like a crescent, sometimes in two parts, always open below, always red with blood vessels. Its use is unknown. The book conjectures that it may be erectile, influencing the eye’s adaptation to different densities and distances, but admits the uncertainty. It is a small reminder that the system, for all its confidence, still had its gaps.
Themes
The deepest theme of the book is the relation between environment and form. Fish are presented from the first page as creatures whose whole organisation is a response to the medium they inhabit. Suspended in a fluid nearly as heavy as themselves, they need no wings; their limbs shrink, their tails take on the work of propulsion, their skins become smooth or scaly. Because they breathe through the intervention of water alone, their blood is cold and their vitality low. Because they live in the empire of silence, their ears are reduced to mere sacs and membranous channels. The book reads the fish’s body as a record of the conditions under which it lives, and in doing so it offers a quiet, pervasive argument about the intelligibility of nature—the conviction that if one understands the medium, one can deduce the creature.
A second theme is the poverty of fish experience, and the book treats it with something close to melancholy. Of all vertebrated animals, fishes show the least signs of sensibility. Their immoveable eyes, their fixed osseous faces, their members without inflections moving only as wholes, have no play in their physiognomy and no expression of emotion. They are destitute, or nearly so, of voice and of all the sensations that faculty awakens or supports. Their pleasures can be but little varied; the sufferings they may apprehend from without are nothing more than pain from actual wounds. This is not cruelty on the author’s part but a kind of sober wonder that so much intricate machinery should serve so narrow a range of feeling—that the whole apparatus of fins and gills and jaws should be devoted, in the end, to the single business of devouring and not being devoured.
A third theme is the sheer abundance and variety of the living world, and the difficulty of doing justice to it. The book is full of numbers: hundreds of thousands of eggs in a single roe; sticklebacks appearing every seven or eight years in surprising quantities and ascending the river Welland in thick columns; sheep’s-heads taken by the hundred at a single cast of the net; carps said to attain the age of more than a century. Against this abundance stands the equally insistent fact of destruction—the far greater number of young that perish, devoured by larger fish, aquatic birds, and reptiles. The catalogue form itself becomes a way of registering both truths at once: the endless multiplication of forms and the endless attrition that keeps them in check.
A fourth theme, quieter but persistent, is the commerce between natural history and human life. The book is full of fish as food, fish as merchandise, fish as the subject of law and legend. The red mullet is remembered for Roman dinner tables; the sea-wolf for Icelandic industry; the sheep’s-head for the ice-packed shipments that hurried it to New York markets at night. The whale-oil trial stands at the head of the whole enterprise as a reminder that definitions matter outside the study. And the fabulous centriscus of Theophrastus, absurdly numbered among creatures springing from corruption, is mentioned only to be dismissed—a small piece of folklore cleared away by the advance of exact knowledge.
The Author’s Conclusions
The book’s conclusions are not gathered into a single peroration but are distributed through its long course, and they are conclusions of method as much as of fact. The most explicit is the argument about definition: that the naturalist’s phraseology, embracing exact definitions that cannot be evaded or misinterpreted, ought to be admitted into legislation, and that the vagueness often reproached to legal instruments would be obviated by it. The whale-oil case is the proof in point, and the definition of a fish as oviparous vertebrata respiring exclusively through water is offered as the model of what such a definition should be.
On the nature of fishes themselves, the book concludes that they are the least sensitive of the vertebrated animals, that their lives are governed almost entirely by hunger and the chase, and that their whole organisation is subservient to progression through a heavy medium. It concludes also that their growth and longevity vary enormously—some continuing to grow nearly all their lives, others, like the carp, said to reach the age of more than a century—and that their reproduction, whether by spawn scattered in the water or by eggs carried about until hatched or by young brought forth alive, is everywhere prodigal and everywhere attended by enormous loss.
On classification, the book concludes that internal structure is the surest guide, and it demonstrates this conviction by the patient subdivision of Linnaean genera into smaller and more exact ones. It concludes, too, that the boundaries between families are often bridged by intermediate forms—that the mailed-cheeked fishes establish a passage from the perches to the drums, that the Sebastes resemble the Serrani so closely as to be confounded with them, that the Sciaenoides share nearly all the external characters of the Percoides while differing internally in their complicated air-bladders. The system, in other words, is not a set of walls but a set of gradations, and the naturalist’s task is to trace them as faithfully as he can.
And the book concludes, finally, by simply continuing. Its last pages are still in the middle of the great catalogue, still defining genera and listing species, still noting which fish are esteemed as food and which are indifferent, still recording the observations of travellers and the corrections of editors. There is no summing-up, no farewell to the reader. The work ends as it began, in the presence of the next genus to be described—an ending entirely in keeping with a treatise whose subject is inexhaustible and whose method is accumulation.
Significance
The significance of The Class Pisces lies first in what it represents: the mature phase of a science that had learned to organise the natural world by structure rather than by resemblance. The book’s insistence on internal anatomy as the basis of classification, its careful separation of the truly cartilaginous fishes from the merely fibro-cartilaginous, its repeated subdivision of over-large genera, and its attention to such diagnostic details as the air-bladder, the fin-rays, and the bones of the cheek—all of this marks it as a product of the comparative-anatomical revolution that reshaped zoology in the early nineteenth century. To read it is to watch a system being built, genus by genus, on the evidence of the dissecting table.
Its significance is also practical. The book is a working manual as much as a theoretical treatise. It tells the reader which fish are good to eat and which are not, where the great fisheries are, how the catch is preserved and shipped, and what the market prices are. It records the migrations of the mackerel and the habits of the stickleback, the nesting behaviour of the goby and the leaping of the Periophthalmus over the mud of the Moluccas. For the nineteenth-century reader with an interest in the sea, it was a compendium of useful and curious knowledge, and for the historian it is a record of how natural history and economic life were intertwined.
Its significance, finally, is literary as well as scientific. The book is written with a clarity and a quiet dignity that make it something more than a reference work. Its account of the poverty of fish experience—the immoveable eyes, the fixed osseous face, the empire of silence—has a reflective quality rare in technical writing. Its anecdotes, from the Roman mullet to the New York whale-oil trial, give it a human texture. And its sheer inclusiveness, its willingness to name and describe and place every creature brought before it, makes it a monument to a particular kind of intellectual patience: the patience of a science that believed the world was orderly, that every fish had its proper place, and that the work of describing them all was worth doing.
