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 enquired 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 an

other 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

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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

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 crustaceous 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.

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 Müller'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

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, "notice these animals in the herrings 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.

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

as the conclusion would be, from the white of an egg being found in a single human stomach after breakfast, to conclude that the race lived solely upon eggs.

But to return to the roe-aals. These animals seem to be, if not the same, at least very nearly approaching to the identical food which, according to Dr Knox, gives the herring its value, and the Dutch their superiority in curing this fish. In a note to Lacepede's account of the herring, which is similar to that of Bloch, his ingenious editor adds an explanation in regard to what the roe-aal of the fishermen of Norway really are. I quote the passage." These are not worms," says he, "but minute shrimps, which are found in the intestines of the herrings fished on the coasts of Norway. This species of crustacea, described by M. Fabricius under the name of Astacus harengum, and which the Norwegians call aal and sil aal, is so multiplied during summer, that thousands of these animals are found in a bucket of sea-water. They serve as the food of fishes, and principally of the herrings, which follow them wherever they direct their course, wherever the wind or current drives them. M. Stroem attributes to the eyes of these shrimps, which contain a deep red fluid, the reddish colour of the excrements of the herrings, a tint which is communicated even to the belly."-Sonnini's Buffon, vol. lxvii.,

p. 15.

Lacepede, in the same article, says that "the food of the herring, to which it owes its rich and agreeable taste, consists generally of ova of fishes, minute crabs, and worms.". Ibid.

M. Fabricius, the author alluded to in the foregoing extract, published his "Species Insectorum" in 1781. His character as a naturalist, and that in a department peculiarly his own, is of the very first order. The minute shrimps, which were ascertained to form a chief part of the food of the herring on the coasts of Norway, he thus describes :

"Astacus harengum, antennis posticis bifidis porrectis, rostro subulato, oculis globosis prominentibus. Habitat in Oceano Norwagico copiosissime, harengum et gadorum esca."-Vol. I. p. 511.

"Gammarus esca, manibus adac

tylis, cauda articulata subulata apice fissa. Habitat in Oceano Norwagico. Harengum cibus gratissimus."—Ibid. 518.

Here, I take leave to remark, are no doubtful conjectures upon a halfdigested animal of dubious identity; but scientific descriptions of the minute or microscopic shrimps upon which the herring was known to feed, enabling future observers to identify the species.

In almost all of the herring stomachs, now on the table, fragments of minute crustacea were found in considerable abundance. There were evidently more than one species.

Latreille, the most celebrated of modern entomologists, in his History of Insects, Paris, 1798, records the Gammarus esca of Fabricus as the food of the herring. The Astacus harengum of the same author he refers to a new genus, Mysis, and states that it has been found on the coast of France.

In the Dictionnaire des Sciences Naturelles, and under the head Clupea, M. Hippolyte Cloquet says of the herring, "Il se nourrit d'œufs de poissons, de petits crabes, et de vers." (IX. 428.) And Bosc, in the "Nouveau Dictionnaire d'Histoire Naturelle," says, "Ils vivent de petits poissons, de petits crustaces, de vers marins, de mollusques, &c. et ils servent de nourriture à tous les cétacés, et à tous les poissons voraces qui habitent les mêmes mers qu'eux."-(XIV. 198.)

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In Gmelin's edition of the Systema Nature of Linnæus, the translation of which, by Dr Turton, published in 1802, it was certainly in Dr Knox's power to have consulted, the Astacus harengum and Gammarus esca of Fabricius are mentioned as the food of the herring-the last species, indeed, as the chief food of herrings.". (III. 761.) And in the "British Zoology" of Pennant, not unknown to Dr Knox, if we may judge so from his referring to this work, that excellent naturalist says, regarding the food of the herring, "What their food is near the Pole, we are not yet informed; but in our seas they feed much on the Oniscus marinus, a crustaceous insect, and sometimes on their own fry. The herring will rise to a fly. Mr Low of Birsa, in the Orkneys, assures me that he has caught many thousands with a common trout-fly, in a deep hole in a rivulet into which the tide

flows. He commonly went at the fall of the tide. They were young fish, from six to eight inches in length."(Pennant, III. 448.9. Lond. 1812.)

The Reverend George Low, in his posthumous work, entitled Natural History of Orkney, published by Dr Leach in 1813, confirms this state ment (p. 227); and Dr Macculloch corroborates these in a paper published in Brande's Journal of Science in 1823. When they (the herrings) first arrive, and for the apparent purpose of spawning, they are not in shoals. They cannot be taken in nets from their dispersion. But the Highlanders then fish them with a feather or a fly, and a rod, and by this very amusing fishery, they take them in sufficient quantity to render it a profit able occupation; as one man has been thus known to take a barrel and a half, or about 1200 fish, during the few days this fishery lasts."-(XVI. 221.)

Dr Neill, in a List of the Fishes of the Forth, published in the Wernerian Transactions in 1811, states his having found" in the stomach and œsophagus of a large female herring no fewer than five young herrings (not sprats) the lower partly dis. solved, the others entire." And he adds, that "when in Shetland in 1804, I met with people who had occasionally taken herrings when fishing for piltocks or coal-fish with limpet bait."-(I. 545.) I myself once found in the stomach of a large herring two partially decayed young fishes of the same species. And there is now on the table (No. 6), a stomach of a herring taken this summer, containing a young animal of the same or some allied species.

Sir John Barrow, in the article Fisheries, printed in the Supplement to the Encyclopædia Britannica, gives it as the result of his enquiries that the herring "fattens on the swarms of shrimps and other marine insects" which abound in the Northern seas (IV. 257). And Mr Wm. Scoresby states the swarms of minute medusa which are found in these seas, and even colouring the water, as beyond calculation. "The fin-whales and dolphins (says he) " feed principally on herrings, and other small fishes. These subsist on the smaller cancri, medusæ, and animalcules." (Arctic Regions, I, 546.) "Thus," continues

he, "the whole of the larger animals depend on those minute beings, which, until the year 1816, when I first entered on the examination of the seawater, were not, I believe, known to exist in the Polar seas. And thus we find a dependent chain of existence, one of the smaller links of which being destroyed, the whole might necessarily perish."—(I. 546.)

Dr Macculloch also states the minute meduse to form part of the food of the herring, on the coasts of Britain. "Among that food" (says he) "we may reckon the medusa, and other analogous marine vermes, which are produced in such abundance in all these shallow seas."-(Brande's Journal, XVI., London, 1823.) And in the volume of the same Journal for 1829, he remarks" If the stomachs of these fishes are widely examined, they will not be found empty, though we cannot detect organized forms in them, as we find entire crabs in the stomach of a cod-fish. Nor is this surprising, when we consider how small and how tender the tribes of marine worms and insects are, and how rapid is the digestive power of fishes."—(Quart. Journal of Science, 1829, p. 134-5.)

I now come to the volume of the Highland Society Transactions for the year 1803, which is referred to by Dr Knox in support of his assertion that, prior to his assumed discovery in 1833, the food of the herring was totally unknown. Before stating what this volume contains on the subject, although including the opinion of a Professor of Natural History, I must take leave to state, that, supposing the authors of the papers in this valuable work to have decided that the food of the herring was to them totally unknown, yet this dictum, in place of proving the fact, would only have proved their ignorance of what had been previously written upon the subject. After what I have already stated as to the numerous authors who have mentioned and described the food of the herring-not even the opinion of Dr Knox, nor Professor Rennie of the King's College, London, celebrated as they are or may be, can weaken their testimony. They may choose to shut their eyes in sunshine and fancy it to be dark. The only inference to be drawn from such state

ments is probative of the ignorance of those who make them.

Here I cannot help noticing the ignorance of the natural sciences which this volume indicates as prevailing even among well-informed men in other respects. There is more information regarding the natural history of the herring in the work of Neucrantz, published 150 years previously, than is to be found in these papers. And it is but justice to my learned friend, Professor Jameson, to say, that it is only since his appointment to the chair of natural history, and the establishment of the Edinburgh Museum, that that taste for the study of nature in this country has been excited, which has led to so many spendid additions to our knowledge.

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The Rev. Dr Walker, in a paper on the natural history of the herring, in vol. ii. of the work referred to, and whom Dr Knox characterises as a strictly correct, scientific, and candid person," observes that "he had examined the stomachs of herrings at different seasons of the year without finding in them any sort of palpable aliment."(P. 274.) "On their first appearance off the Lewis, in the month of July, when they were full grown, and very fat, nothing appeared in their stomach but a little slime."—(P. 275.) “ During the residence of the herrings on the coast of Scotland, we know of no food they use, and it is probable they require little or none, except some attenuated alimentary matter which the sea-water may afford them."-(P. 275.) "We think it not altogether improbable that they may live on a small species of medusa, or some similar marine animal, which is not as yet known to naturalists." (P. 276.)

Here Dr Knox confines himself, in the quotations he gives from Dr Walker's paper, to extracting such sentences as imply the food of the herring to be totally unknown. But this is not the way, were the matter at all doubtful, to arrive at a just conclusion. I shall give the sequel of the passage in Dr Walker's words:

"In the ocean, to the north-west, and at a considerable distance from the most northern extremity of the British islands, a vast profusion of a singular substance has been often seen floating on the surface, and that by skilful ma. riners, who were also conversant with the herring-fishery. The different

accounts given to me by these persons agreed in this, that the substance consists of separate globules of a roundish figure, and of the size of a pea, resembles blubber, covers the surface of the sea to a great extent, and makes it to appearance as if covered with oil; that the herrings are known to feed upon it; and that it has been observed in great profusion to the north-west of Shetland, where the herring shoals existed at the time, but has nowhere else been seen on the coast of Scotland. If this account, given by persons of observation and veracity, is admitted, we need be no longer surprised at the retreat of the herrings to those tracts of the northern sea, nor at their return from thence in a full-fed and fat condition. The substance here intimated is probably a small species of the medusa, or some similar marine animal, which is as yet not known to naturalists."—(II. 275, 276.)

Dr Walker seems perfectly right in his conjecture; for Mr Scoresby and Dr Macculloch, as has been already remarked, positively mention species of medusa as the food of the herring. The former states their incalculable numbers in the Northern seas, tinging the water for miles, and gives figures of several species; and the latter states that he has seen large tracts of the Cornish coast, where the "whole sea was almost a mass of life, from the presence of these and other marine animals."-(Jour. of Science for 1830, p. 135.)

In the same volume is a paper, by Mr John Mackenzie, on the fisheries of Scotland, which tends to corroborate the fact of some minute species of medusa forming the food of the herring in certain situations. "Another article of their food" (says he)" is an oozy substance at the bottom of the sea, adapted, it would appear, by the Author of Nature for that purpose. This sometimes appears in calm weather floating on the surface, in the form of small globules, at which fishermen have observed herrings to spring as trouts do at flies."-(P. 314.) These floating globules were, there is little doubt, some small species of medusa, or kindred animal, such as referred to by Dr Walker, and mentioned as the food of the herring by Mr Scoresby and Dr Macculloch; and goes to prove, in addition to what is stated by these writers, that minute molluscous ani.