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ject of such remarks cannot be mistaken."-P. 464.

3. Superlative." Of my competency to make correct anatomical and physiological remarks, no reasonable person, I hope, who is at all acquainted with the nature of my pursuits, will have any doubt."-P. 464.

"The reason why the food (of the herring) could not be discovered by preceding observers, will be readily understood by most of my readers. It was next to an impossibility for any other than a scientific person, who had examined the whole range of the animal kingdom, to make out the enquiry."-P. 514.

The name of the individual referred to in this last sentence, "who had examined the whole range of the animal kingdom," is left to be gathered from the context. Of only one man in Europe could this be said, and that person was the late Baron Cuvier. I need scarcely observe, however, that the writer of this hyperbolical compliment did not mean the author of the Règne Animal.

The process of reasoning which led to the supposed discovery, is not less singular than the discovery itself. Ascertaining that a fresh-water fish from the south of Scotland had some resemblance in size and general appearance to the herring, the author concluded, that if he could find out what the vendace fed upon in Lochmaben loch, the food of the herring, though living in a different element, the sea, would most likely be the same. Vendace were, of course, caught, their stomachs were examined, and animalcules such as are found in lakes and ponds were there detected by the microscope. The sagacity of the conjecture was now fully evidenced; and an animal, which the vulgar thought lived by the suction of air or water, was really found to feed upon the minute animals which existed in the loch with them. First, one species of animalcule was found in a stomach examined, and at a different period another. Here the enquiry as to food stopped, which, to have done justice to the subject, should have been spread over the whole year, and have embraced the food of all seasons.

From this, the transition to the herring and its food, supposed to be equally unknown as that of the vendace, was, according to Dr Knox, na

tural, and the examination of the sto mach of the herring was, of course, de termined on. "The discovery of the food of the vendace," he exclaims, "decides the question as to the food of the herring."-P. 507. The herring of the German Ocean, at least one specimen, was found to have in its stomach the fragment of a crustaceous animal, which the author considered to be of the same species or genus as that found in the stomach of the vendace of Lochmaben ; and to this peculiar food both fishes were said, on the faith of this analogy, to owe all their value as articles of food.

Had an analogy been attempted between the vendace and salmon, it might have been intelligible, as both belong to the same natural family, and both inhabit occasionally the same medium. But to attempt to draw any analogy between the vendace and herring, fishes of different natural fami. lies, and inhabiting different mediums, which neither ever quits, seems, if I may be allowed to make use of the comparison, much akin to the resemblance discovered by Captain Fluellen, between the birth-places of Alexander the Great and King Henry V. "There is a river in Macedon; there is also, moreover, a river at Monmouth: it is called Wye, at Monmouth, but it is out of my prains what is the name of the other river; but it is all one; 'tis as like as my fingers to my fingers, and there's salmons in both."—Henry V., Act IV., Sc. 13.

Let it be granted, however, that this wide analogy, by some peculiar process in the mind of the author, led him to discover the mutilated remains of a minute crustaceous animal in a herring of the German Ocean, from having previously found minute animals of a different species in the stomach of the vendace of Lochmaben to what does the discovery amount? To the truism, that the vendace, like all the animals of the same class, feeds upon what it finds in its native waters, and these animalcules among the rest. Reasoning à priori, any naturalist would have predicated the kind of food the vendace had to choose upon in such a piece of fresh water; and, in point of fact, the writers upon these minute inhabitants of lakes and rivers assign them generally as forming part of the food of fishes." They (the cyclops)

serve (say Bosc and Latreille), as the other animals of the division Entomostraca, for the food of all aquatic insects, all the vermes which inhabit the same places, of many fishes, and birds.”Nouv. Dict. d'Hist. Nat. IX. p. 29. And Leuwenhoek, giving a magnified representation of one of the animals upon which the fishes of lakes feed, and that example exactly the same species which Dr Knox, more than a hundred years after, found in the stomach of the vendace, states positively that these "pisciculi minores," as he calls them, "facti sunt ad alimentum majorum."-Vol. III., p. 145. Now, if a major proposition necessa rily includes the minor, then the food of the vendace, as well as other freshwater fishes, was known to Leuwenhock; and Dr Knox has only the merit of applying a general principle to a particular case.

I readily concede to Dr Knox all the merit, if there be any, of finding first one animal, and then another, in the stomach of the vendace; but he has stated no facts regarding its food in general, or at different periods of the year, when the Daphnia and Cyclops (for such appear to be the animals whose fragments he has figured) are not to be found. And there can be little or no doubt that, if examined at different periods of the year, the larvæ of insects, and other inhabitants of the lake, would be found to be the prey of the vendace, as of other freshwater fishes.

Mr Yarrell, in vendace from the same lake, found in the stomach the Lynceus roseus of Desmarest, the Monoculus roseus of Turton, and the Cyclops vulgaris of Leach, or the Monoculus quadricornis, Lin.; together with a very small coleopterous insect, the tough skin of a red worm, and what appeared to be a portion of the wing of a dipterous insect.—(British Fishes, Vol. II.) And the pollan of Lough Neagh, in Ireland, a species of coregonus, if not exactly the same as the Lochmaben vendace, feeds on all the varieties of aliment which the lake affords.

But this discovery of the food of the vendace is as nothing, when compared with the most unexpected communication by which it is followed, that this species of fish really consisted of two sexes, male and female; and that this anomaly required to be proved to the Royal Society. In the published ab

stract of his paper, drawn up by himself, Dr Knox says, he "proved the vendace to be male and female!" The Doctor has not detailed in this instance the steps which led to this discovery, nor the analogies which induced him to hazard such a startling proposition; and it really seems not very creditable to the previous knowledge of one "who had examined the whole range of the animal kingdom," that he should for one moment suppose the vendace of Lochmaben to be brought into existence without the participation of a male parent. On this point the analogy of all vertebrated animals was in favour of the presumption; and even inferences, drawn from some of the vegetable tribes, might have indicated, to a mind more obtuse than the Doctor's, how the great work of reproduction was carried on among fishes. But really it is impossible gravely to consider this discovery. Why, the very fishwomen in the Edinburgh market would have laughed at the annunciation. They could have told the Doctor that a hen-lobster necessarily implied the existence of a cock-lobster; that where there were cock-padles, there must also be hen-padles; and on the same authority he might have learned, that a maiden skate (no great rarity in the market), was typical of a flat fish that had not been a mother.

I come now, in the second place, to examine the claims of Dr Knox as the discoverer of the food of the herring (Clupea harengus, Lin.) "Modern systematic writers," says he, " on natural history, maintain a profound silence as to the food of the herring.". P. 513. "In 1833, Professor Rennie, of the King's College, London, declares the food of the herring to be altogether unknown."-Ib. "It was next to an impossibility for any other than a scientific person, who had examined the whole range of the animal kingdom, to make out the enquiry."-P. 514.

Now, in opposition to what is asserted in these sentences as to the food of the herring being "altogether unknown," I venture to state, and the statement will be borne out by the evidence of almost all writers on the natural history of fishes, that the food of the herring was perfectly well known, and published, many years before the period of the appearance of this paper. In place of taxing his mind with

a far-fetched analogy, and taking a circuitous route to enhance the merit of his supposed discovery, if the author had taken the trouble to open almost any one of the systematic works which he says maintain a profound silence on the subject, he would have seen that there was no mystery in the matter; he would have seen that the food of the herring was better known than the food of almost any other fish; and that every circumstance which he has recorded as the fruits of his "patient scientific enquiry," might be found in the published works of preceding writers.

Before proceeding, however, to notice what has been written upon this subject by preceding enquirers, it is necessary to remark, that Dr Knox's discovery of the animal which forms, he asserts, the food of the herring, rests on a mutilated fragment of a minute crustaceous animal, which he has figured, found in the stomach with other remains of food; and from this he concludes that the said animal is the exclusive food of the herring, to which it owes all its good qualities; and, to use his own language, "when it takes to other food, it is good for nothing as - an article of food." How the Doctor makes out all these consequences from the single fact he details, we are not informed. To give any thing like probability to these suppositions, it would be requisite, in the first place, to prove the existence of such animals in the seas which herrings frequent, in sufficient numbers to supply the innumerable shoals with this their peculiar food; and, secondly, it would be necessary to show in what respects, or in what manner, other species of food acted so injuriously upon the fish as to make its body run rapidly into putrescence. Without stopping to notice further these generalizations, based on the detection of a single fragment of an animalcule in the stomach of a herring, I shall proceed to lay before the Society a few of the notices of preceding naturalists as to the food of this valuable fish.

The first author to whom I shall allude as having discovered and mentioned the food of the herring, is Paul Neucrantz, doctor in philosophy and medicine, and physician at Lubeck. This gentleman wrote a dissertation on the herring, which was published at Lubeck in 1654, under the follow

ing title:-" De Harengo, Exercitatio Medica, in qua principis piscium exquisitissima bonitas summaque gloria asserta et vindicata." This work contains a very full and learned account of the herring, the time of its appearance on the Northern and British coasts, the mode of preparing it for exportation; in short, a complete natural history of this valuable fish and its economical uses. The fifth chapter of this work is devoted to the refutation of the vulgar notion that the herring subsisted on sea-water, and that generally nothing was to be found in its stomach. Describing that viscus, and showing from its structure that it was calculated to be the recipient of solid food, he goes on to state that it is not always empty, as supposed, but often crammed with food; and that he had frequently ascertained the nature of this food from personal inspection, and sometimes counted upwards of sixty minute squillæ, or shrimps, in one fish, and many of these partially digested. He states further, that when the spawning was completed, there was less food found in the stomachs of the spawned fish; that in these the intestine appeared to be half-filled with the ova of other fishes, or their own; and he gives it as his belief that the herring feeds on its own fry, when languid and exhausted from spawning.-Neucrantz De Harengo, p. 28.

Neucrantz died in 1671. A copy of complimentary verses, by the classical Meibomius, is affixed to his work.

In order that it may be understood what the squilla of the writers of the period were, I have laid on the table the Historia Naturalis of Johnston, in which all the then known species are represented.

The next author I have met with who ascertained the food of the herring is Antony Leuwenhoek; and when I mention this name, it is a warrant to this Society, and to every one to whom the literature of science may be but slightly known, for the value of his observations. At the same time, it is but fair to state, that Dr Knox, aware, perhaps, of the loose foundation upon which his asserted discovery rests, takes an exception to any evidence that may be adduced against him, in these not very complimentary terms:— "I am aware," says he, "that there are many, whose regard for accuracy in

scientific statements being extremely coarse and loose, will not only assert that they had examined the stomach of the herring, but had also seen its food."-P. 515. Notwithstanding this civil insinuation of mendacity on the part of those who presume to take up a contrary opinion to the Doctor, I state with confidence the testimony of Leuwenhoek.

What led Leuwenhoek to the investigation of the food of the herring, was the circumstance of this fish, not very fat in appearance, having the intestines covered and the body saturated with fat, while other sea fishes, however thick in the body, secreted none of this fatty matter. This induced him to investigate the nature of the food of the herring; and, having en quired at various fishermen on the coast of Holland what food they found in the stomach, was told, as any enquirer here would be told, "se nunquam ullum in halecum stomacho aut intestinis reperisse cibum." (Epist. p. 46, 47.) Not discouraged at this, he went to market about the middle of March, and purchased a few berrings, in the second of which he found a reddish matter, which he discovered by the microscope to be composed of rounded bodies, scarcely acted upon by the stomach. The same bodies, which appeared to be minute sacs, were found in the stomachs of all the herrings. "Hence it did not appear to me wonderful," says Leuwenhoek, "that the fishermen should conceive that no food was to be found in the stomachs of herrings, because they feed on animals so minute, and not in sufficient quantity at a time to distend the stomach, as we see in other fishes." "While other fishes are able to fill their stomachs so as to constitute a fifth part of the size of the animal, and the fragments of the food remain even for days in this viscus, the herring, on the contrary, is constantly swallowing those minute animalcules which escape the eye of the fisherman." On another occasion Leuwenhoek examined the stomachs of herrings when many had spawned, and found in the chyle and intestines the ova of their own species. At a different period he found


substances which he conjectured to be vegetable; other slender oblong particles, of which he could not satisfactorily ascertain the nature; along with what appears from his description to be a minute Asterias. (II. Epist. 97, p. 52.)

In proof of the accuracy of Leuwenhoek's statement, there is now on the table the intestinal canal from a salt herring, filled with half-digested ova (No. 1.) And in two other specimens (Nos. 2 and 3), taken this summer, ova in a forward state of developement were clearly distinguishable. Whether these are ova of the herring or not, I am not prepared to say.

The result of Leuwenhoek's enquiry was, that it was evident to him that herrings not only fed on animalcules, minute fishes, or aselli, and even on their own ova, but also, when pressed by hunger, any thing they met with. (P. 53.) Leuwenhoek goes on to state, that, considering the nature of the food and the shoals to be fed, there must be in the sea incalculable numbers of minute animals, beyond what had been imagined. In another place he states that the sandy shores of Holland abound with these minute crustacea. And he accounts for the shoals of herrings moving to different parts of the coast by attributing their presence to the plenty or scarcity of food-" ad escam congregantur aquila."

Here, then, the food of the herring is ascertained, by one of the most suc cessful investigators of the arcana of nature, to consist of "exigua animalcula, sive pisciculos," and, in default of other food, he ascertained that they even swallow the ova of their own species. The letter which contains this investigation is dated at Delft, in Holland, in January 1696.*

The next writer, of those which have fallen in my way, who mentions particularly the food of the herring, is the celebrated Otho Frederick Müller, who published a work, entitled "Entomostraca, seu Insecta Testacea," in 4to, at Leipsic and Copenhagen in 1785. In that work, he describes a species of Cyclops under the name of Cyclops longicornis, which he says was found in the sea of Finmarck, by the

Atque ita mihi conspicuum fuit, haleces non tantum vesci exiguis pisciculis, atque etiam propriis ovis, sed et quodcunque obvium urgente necessitate, versus stomachum demittere."

celebrated Gunner, and afterwards "in sinu Drobactiorum," by himself, in numbers, in the stomach of a herring, without particularly looking for any such thing. This small crusta. ceous animal is figured by Müller in his 19th plate, fig. 7-9. Dr Knox confesses, that the fragment of the crustaceous animal which he found in the stomach of a herring, "approaches very nearly the Cyclops of M. Dumeril;" and bears "a strong resemblance" to the animal found in numbers by Müller, in the stomach of the same species of fish.

class of voracious fishes. It lives chiefly on minute crabs" (crustacea). "Neucrantz," says he, has found many in its stomach half digested. Leuwenhoek has also observed ova of fishes in the œsophagus. It also feeds on worms; and the fishermen of Norway have often found its intestines filled with a species of red worm, which they call roe-aal. When the stomach is full of these animals, they believe that the fish is diseased; but the true explanation is, that these worms, being much more subject to decay, spoil the herring before it is salted." Then Bloch explains, on the principle of the known rapid digestion of the herring, why their stomachs are generally found empty when caught. "Whenever the fishermen," says he,

they are taking, they leave them during some time in the water, that the food may be entirely digested, and the fish, of course, keep better when salted.”— Bloch, vi. p. 252, 253.

The animal represented by Müller is then either of the same species as the fragment figured by Dr Knox, or it is not. If it be of the same species, there is an end to Dr Knox's claim, for this very good reason, that Mül-"notice these animals in the herrings ler's work was published in 1785, and Dr Knox's supposed discovery was not made public till 1833. Nay, more, Müller refers to a previous writer, who had discovered this animal in the sea of Finmarck many years before; and he himself had described it under the name of Cyclops Finmarkii, in the "Zoologiæ Danica Prodromus," which was published at Copenhagen in 1776. The "immortal Gunner," whom Müller mentions as its first describer, had previously given a figure of the animal in the 10th volume of the Copenhagen Transactions.

On the other hand, if it be not the same animal as those figured by Gunner and Müller, then it must assuredly be a fragment of one or other of the minute crustacea, which, along with other minute animals and ova, are stated by Neucrantz and later naturalists to form the food of the herring, and which abound on all the northern shores.

How the Doctor could give a figure of the "natural size of the adult, fullgrown animal," to use his own pleonastic expression, from an imperfect fragment, he does not explain ;-but the deficiency could easily be supplied from Müller's figure.

The next writer I notice who mentions the food of the herring, is the celebrated ichthyologist, Mark Eleazar Bloch, who began to publish his superb work on fishes at Berlin in 1785. In his account of the herring he thus writes: "The herring, which is so often exposed to the voracity of other animals, belongs itself to the

It is necessary here to mention that the modern class Crustacea, in which minute crabs and shrimps are included, made part of Linnæus' great class INSECTA, and were arranged under the generic name of Cancer by that illustrious naturalist. The term worms (VERMES) of the same author, besides the worms properly so called, included the testaceous as well as naked mollusca, and zoophytes. And hence, by all the writers of the period we are considering, the terms minute crabs, worms, and insects, include all the animals now separated into divisions more precise, and more accommodated to the extended state of our knowledge. Thus, the crabs, lobsters, and shrimps, &c., form the modern class CRUSTACEA, the radiated animals are arranged under the class ECHINODERMATA, and the one-eyed animals, which Linnæus brought together under the generic term Monoculus, are now included in the sub-class ENTOMOSTRACA, a term applied to them by Müller. A great portion of the animals of these classes form generally the food of fishes, and some species have been more particularly ascertained to be part of the food of the herring. To limit its food, however, to this or that species, on the evidence of a single fragment, or thousands of fragments, at one season of the year only, and on one particular coast, is pretty nearly as philosophical

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