Part 8

If, however, we are right in assuming that a given area of ground can only produce a given weight of fish per annum, it is fairly certain that, under protection, the increased density of the fish inshore will result in a retardation in the average rate of growth, an example of which we have given on a previous page. This must produce one or other of two results: either the small fish will remain longer on the inshore grounds before emigration, or they will emigrate offshore at a smaller size than at present. Judging, therefore, from the evidence available, it seems probable that legislative restrictions on the lines indicated can do little to replenish the offshore fishing-grounds, while such restrictions may lead to a slight, and possibly a substantial, increase in the number of small boats fishing along the coasts affected.

While Great Britain can grudge no benefit to the fisheries of other countries, it is the improvement of the deep-sea fisheries which is the paramount interest of this country. Doubts, it has been said, are resolved by action; but if we have correctly analyzed the complicated factors which affect this problem, we have also shown how essential to right action is the fullest possible knowledge concerning all the factors involved. Grave as the North Sea problem undoubtedly is, it is equally certain that the condition of the fishing industry generally was never more prosperous than at the present time. The figures quoted in an earlier part of this article prove this statement to be no paradox. Interference of some kind, whether by legislation, transplantation, artificial culture, or some combination of all these means, seems ultimately to be inevitable. But, if we are to interfere with the fishing industry more successfully than our predecessors, we should take advantage of the present time of prosperity to increase our knowledge on every side--scientific, statistical, experimental--so as to be able to act with conviction when the whole circumstances are clearer and the adequacy of our proposals is less open to doubt. Moreover, in view of the growing interest of other countries, especially Germany and Holland, in deep-sea trawling, and of the international character of the most critical problems, there can be no two opinions as to the desirability of continuing these investigations on some kind of international basis, a basis which has already been productive of very promising results.

Before turning our attention to the various bodies which administer and investigate the fisheries of England, a short consideration of what is done in the two great countries which have scientifically developed their fisheries may be profitable. In Germany we have the Kiel Commission, and in the United States the Commission of Fish and Fisheries. The Kiel Commission exists for the scientific investigation of the German seas. It was established in 1870 at the suggestion of a German sea-fishery society--an interesting example of the belief which the German layman has in science. It consists of four Kiel professors--Hensen representing physiology, Karl Brandt zoology, Reinke botany, and Krümmel geography--and of Dr. Heincke, director of the biological station on Heligoland. An annual grant of £7,500 is made by the German Government for the maintenance of the laboratories at Kiel, the cost of steamers for investigations, the cost of the handsome reports published under the name of ‘Wissenschaftliche Meeresuntersuchungen,’ and for salaries; of these the five members of the Commission divide but £270 between them. The German Government has also spent considerable sums on the biological station in Heligoland, and make it an annual allowance of about £1,000.

The American Commission, like that of Kiel, is not an administrative body, but concerns itself with the acquisition and application of knowledge concerning fisheries; like it, too, it is independent of official control. It reports directly to Congress. It was established in 1871. Its work is, however, of a more practical kind; besides general scientific investigation, it collects fishery statistics and undertakes commercial fishery inquiries, assists in finding markets, and generally advises the trade and the Legislature when diplomatic action is indicated; finally, it is by far the most energetic fish-breeding institution in the world. Much of its work is concerned with the vast system of inland waters--rivers and lakes--which traverse the Continent. The work has been carried out on a scale unknown elsewhere, and Congress has supported it with ample funds. The appropriation in 1897-1898 exceeded £97,000, of which £41,000 was spent on salaries, £16,000 on scientific investigations and upkeep of steamers, £37,000 on fish-culture (mostly fresh-water), and £3,000 on administration and statistics. Besides this central body, many of the States possess fish commissions of their own. The commissioners control numerous laboratories and fish-hatcheries, two sea-going vessels, and many railway-cars specially designed for the transport of fish-fry.

Space does not permit our dealing with the Scottish and Irish Fishery Boards. The former has existed for a century, and, being independent of departmental control, while enjoying a moderate income and the advice of such zoologists as Goodsir, Allman, Sir John Murray, Cossar Ewart, W. C. McIntosh--who has done more than anyone in the Empire to elucidate the life-histories of marine fishes--and D’Arcy Thompson, together with an able staff, the Fishery Board for Scotland has done much thorough and useful work. The fisheries of Ireland suffered from the economic disturbances which overtook Ireland during the nineteenth century, and reached, perhaps, their lowest ebb in 1890. The industrial revival, with which the name of Sir Horace Plunkett is so indissolubly connected, has included in its scope the Irish fisheries. The fishery branch of the Department of Agriculture and Technical Instruction receives an annual grant of £10,000, and, under the guidance of the Rev. S. Green and Mr. E. W. L. Holt, is already doing much to promote the fishing of the well-stocked Irish seas.

The English official fishery staff seems to have sprung from the requirements of the Salmon Fishery Act of 1861. To carry out the regulations over fresh-water fisheries recommended by that Act two inspectors were appointed, and these were at first attached to the Home Office; a further Act in 1886 transferred these inspectors to the Board of Trade, and extended their duties so as to include the preparation of annual reports on sea-fisheries. In 1903 another transfer took place; and the inspectors were transferred to the Board of Agriculture, which then became the Board of Agriculture and Fisheries.

At present the central staff consists of an assistant secretary and two inspectors, in addition to a body of statistical experts. Their duties are far too numerous for so small a staff. Much of their time is taken up with the comparatively unimportant fresh-water fisheries; and these are the subject of a separate report. Without actually administering the byelaws of the local committees, they exercise a certain supervision over their actions. They have to attend numerous inquiries all over the country, and to prepare annual reports; and they are responsible for the collection of the statistics which have recently assumed so extensive a development. Besides the central authorities at the Board of Agriculture and Fisheries, there are local fisheries committees established by an Act of 1888. These committees can be established by the county and borough councils on application to the Board of Agriculture and Fisheries, which defines the area over which a committee shall have jurisdiction. One-half of such a committee is chosen by the local councils, and one-half by the central authority. The necessary money is raised by a local rate. A committee may draft byelaws; but these only become operative if confirmed by the Board. These byelaws differ, according to conditions, in different parts of England. They deal largely with restrictions on trawling. No steam-trawler is allowed to trawl within the three-mile limit around the coast of England; even the sailing trawler is forbidden. The byelaws also deal with the sizes of the meshes of nets, shrimping, crabbing, etc.

Neither the central authorities, whose chief function is to administer the law and collect statistics, nor the local committees, whose expenditure is limited to the ‘shell-fisheries’--and, stretch the Act to the breaking point, you still cannot make a flat-fish into a shellfish--have either the time or the money for scientific experiment. This has to a large extent been left to local or private enterprise, and is mainly confined to three centres--the Northumberland coast, the Lancashire and western district, and the Channel and North Sea. The first-named area has recently been supplied by a private benefactor with funds for an efficient laboratory at Cullercoats, from which much useful work may be expected.

It is difficult to disentangle the Lancashire and Western Sea-fishery Committee from Liverpool University on the one hand, and from the Liverpool Marine Biological Committee or Society on the other. The Committee owns a handsome marine station at Port Erin, on the Isle of Man; here and at the fish-hatchery at Peel, in Cumberland, the largest fish-breeding experiments in England are carried out. In 1904, 5,000,000 young plaice were reared and put into the sea from Port Erin alone. The Committee publishes annual reports and a series of ‘Memoirs.’ It is probably to this Committee that the University owes its connexion with the local sea-fisheries authorities. In the laboratories and museums of the University the scientific work of the local districts is carried on by officials paid by the Fisheries Committee; and special rooms in the handsome new zoological department have been assigned to these two organizations. The connecting link between the three bodies is the professor of zoology, Dr. Herdman, who is honorary director of the scientific work, and to whose untiring energy the University and the district owe a large debt. With him work two trained naturalists, Dr. Jenkins, the Superintendent of the District Committee, and Mr. James Johnstone, whose lucid and admirable work is mentioned at the head of this article. From it many of our figures and facts have been taken.

The third and last body occupied with original marine research is the Marine Biological Association of the United Kingdom. It is the most important of these institutions, and aims at a national rather than a local activity. The fine laboratory which dominates the eastern end of Plymouth Hoe was erected at a cost of £12,000, and opened in 1888. The object of the Association is to ‘promote researches leading to the improvement of zoological and botanical science, and to an increase of our knowledge as regards the food, life-conditions, and habits of British food-fishes and molluscs.’ Although a high average of scientific work has been displayed in the published ‘Memoirs’ connected with the Plymouth laboratory, great attention has also been paid to matters of practical interest. In a list of some 350 papers published, with the aid or under the auspices of the Association, between 1886 and 1900, nearly one-half deal directly with economic problems. From 1892 to 1895 the officers of the Association carried on at Grimsby extensive investigations into the destruction of immature fish; and it is gratifying to find that the Select Committee of 1893 extended its recognition to the ‘facts and statistics’ submitted by the Scotch Fishery Board and by the Association. In the summer of 1902 the Association, at the request of the Government, undertook to carry out the English portion of the International Investigation of the North Sea. The scope of this inquiry is immense; and its importance to the largest fisheries available for our fishermen is incalculable. Some idea of the kind of work accomplished has been furnished in the preceding pages.

What now seems to be most required, in addition to the maintenance of the work already in progress, is a closer co-operation of these various bodies with one another and with the central authority now established under the President of the Board of Agriculture and Fisheries. The outlines of some such scheme seem plainly indicated by the existing constitution of these various bodies. The Fisheries Department is responsible for administration, statistics, and general advice to the President of the Board on fishery matters. The Marine Biological Association undertakes general marine investigations of a national as distinct from a local character, as well as such local investigations and experiments as can conveniently be carried out at its laboratories. The Sea-fishery Committees need additional powers to enable them to carry out local scientific investigations more fully in their respective areas. Perhaps an annual conference between the representatives and experts of these bodies and the officials of the Fishery Department, for the express purpose of drawing up plans of work for the ensuing year, would, in the first instance, be the best means of leading up to more intimate co-operation and organization.

The Reports on the North Sea Investigation so far published deal only with the work of the earlier years of the investigations; but already the great prospective value of the results is fully apparent. The Marine Biological Association has carried out the portion of the general scheme entrusted to it with energy and success; and Englishmen have no need to fear comparison with the work done in other countries.

ZEBRAS, HORSES, AND HYBRIDS

This matchless horse Is the true pearl of every caravan. SIR F. H. DOYLE.

The views and writings of Darwin have influenced in an unexpected way the nature of the work carried on by biological investigators during the past fifty years. To a great extent, whilst generally holding the doctrines he held, they have forsaken his methods of inquiry.

If animals and plants have arrived at their present state by descent with modification from simpler forms, it ought to be possible by careful searching to trace the line of ancestry; and it is this fascinating but frequently futile pursuit which has dominated the minds of many of our ablest zoologists for the last thirty years. To such an extent has this pedigree-hunting been carried that there is scarcely a group of invertebrates from which the vertebrates have not been theoretically derived; and one of the ablest of our physiologists has used his great powers in the attempt to trace the origin of the backboned animals from a spider-like creature, and has exercised his ingenuity in a plausible but unconvincing effort to equate the organs of a king-crab with those of a lamprey. This appeal to comparative anatomy and the consequent neglect of living animals and their habits are no doubt partly due to the influence of Huxley, Darwin’s most brilliant follower and exponent. He had the engineer’s way of looking at the world, and his influence was paramount in many schools. The trend which biology has taken since Darwin’s time is also partly due to a fervent belief in the recapitulation theory, according to which an animal in developing from the egg passes through phases which resemble certain stages in the past history of the ancestors of the animals. For example, there is no doubt that both birds and mammals are descended from some fish-like animal that lived in the water and breathed by gills borne on slits in the gullet, and every bird and mammal passes through a stage in which these gill-slits are present, though their function is lost, and they soon close up and disappear. In the hope, which has been but partially realized, that a knowledge of the stages through which an animal passes on its path from the ovum to the adult would throw light on the origin of the race, the attention of zoologists has been largely concentrated on details of embryology, and a mass of facts has already been accumulated which threatens to overwhelm the worker.

The two chief factors which play a part in the origin of species are heredity and variation, and until we know more about the laws which govern these factors, we cannot hope to arrive at any satisfactory criteria by which we can estimate the importance of the data accumulated for us by comparative anatomists and embryologists. Signs are not wanting that this view is beginning to be appreciated. The publication of ‘Materials for the Study of Variation’ by Mr. Bateson some years ago shows that there exists a small but active school of workers in this field; and recent congresses on hybridization give evidence that in America, on the Continent, and in Great Britain, one of the most important sides of heredity is being minutely and extensively explored. Professor Cossar Ewart’s experiments, which we shall attempt to summarize, deal with heredity and cognate matters, and although they are so far from complete that the results hitherto obtained cannot be regarded as final, they mark an important stage in the history of the subject.

Twelve years ago Professor Ewart began to collect materials for the study of the embryology of the horse, about which, owing to the costliness of the necessary investigations, very little is at present known. At the same time he determined to inquire into certain theories of heredity which have for centuries influenced the breeders of horses and cattle, and the belief in which has played a large part in the production of our more highly bred domestic animals. Foremost amongst these is the view widely held amongst breeders that a sire influences all the later progeny of a dam which has once produced a foal to him. This belief in the ‘infection of the germ,’ or ‘throwing-back’ to a previous sire, is probably an old one, possibly as old as the similar faith in maternal impressions which led Jacob to placed peeled wands before the cattle and sheep of his father-in-law Laban. The phenomenon has recently been endowed with a new name--Telegony. Since the publication of Lord Morton’s letter to Dr. W. H. Wollaston, President of the Royal Society, in 1820, it has attracted the attention, not only of practical breeders, but of theoretical men of science. The supporters of telegony, when pressed by opponents, having almost always fallen back on Lord Morton’s mare, it will be well to recall the chief incidents in the history of this classic animal.

It appears that early in last century Lord Morton was desirous of domesticating the quagga. He succeeded in obtaining a male, but, failing to procure a female, he put him to a young chestnut mare of seven-eighths Arab blood which had never been bred from before. The result was the production of a female hybrid apparently intermediate in character between the sire and the dam. A short time afterwards Lord Morton sold his mare to Sir Gore Ouseley, who bred from her by a fine black Arabian horse. The offspring of this union, examined by Lord Morton, were a two-year-old filly and a year-old colt. He describes them as having

‘the character of the Arabian breed as decidedly as can be expected where fifteen-sixteenths of the blood are Arabian, and they are fine specimens of that breed; but both in their colour and in the hair of their manes they have a striking resemblance to the quagga.’

The description of the stripes visible on their coats is careful and circumstantial, but the evidence of the nature of the mane is less convincing:

‘Both their manes are black; that of the filly is short, stiff, and stands upright, and Sir Gore Ouseley’s stud-groom alleged that it never was otherwise. That of the colt is long, but so stiff as to arch upwards and to hang clear of the sides of the neck, in which circumstance it resembles that of the hybrid.

This is the classical--we might almost say the test--case of telegony: the offspring resembled not so much the sire as an earlier mate of the dam. The facts related tended to confirm the popular view, and that view is now widely spread. Arab breeders act on the belief, and it is so strongly implanted in the minds of certain English breeders that they make a point of mating their mares first with stallions having a good pedigree, so that their subsequent progeny may benefit by his influence, even though poorly-bred sires are subsequently resorted to.

The evidence of Lord Morton’s mare convinced Darwin of the existence of telegony. After a careful review of the case, he says: ‘There can be no doubt that the quagga affected the character of the offspring subsequently got by the black Arabian horse.’ Darwin, however, latterly came to the conclusion that telegony only occurred rarely, and some years before his death expressed the opinion that it was ‘a very occasional phenomenon.’ Agassiz believed in telegony. He was strongly of opinion

‘that the act of fecundation is not an act which is limited in its effect, but that it is an act which affects the whole system, the sexual system especially; and in the sexual system the ovary to be impregnated hereafter is so modified by the first act that later impregnations do not efface that first impression.

Romanes also believed that telegony occasionally occurred. He paid a good deal of attention to the matter, commenced experiments in the hope of settling the question, and corresponded at length on this subject with professional and amateur breeders and fanciers. The result of his investigations led him to the conclusion ‘that the phenomenon is of much less frequent occurrence than is generally supposed. Indeed, it is so rare that I doubt whether it takes place in more than 1 or 2 per cent. of cases.’ He adds that his professional correspondents regard this as an absurdly low estimate. Tegetmeier and Sutherland believe that telegony exists in dogs and other animals; and Captain Hayes, whose opinion probably coincides with that of the majority of veterinary surgeons, takes for granted that it occurs in horses. A controversy some years ago in the Contemporary Review shows us that Mr. Herbert Spencer was a firm upholder of telegony, and that he had a theory of his own as to the mode in which it is brought about.

The explanations put forward by the supporters of telegony as to the mechanism by which it is effected differ widely. It will be well to discuss them here. The view that telegony is due to the mental impression of the dam, held by Sir Everard Home and many others since his day, has nothing to support it; but the other two views, which may be termed (1) the infection hypothesis, and (2) the saturation hypothesis, demand more detailed treatment.

The infection hypothesis supposes that the reproductive organs of the mother are specifically altered or infected by bearing offspring to a previous sire. The method by which this is effected is now most commonly thought to be by a fusion or blending of some of the unused germ-cells of the first sire with the unripe ova in the ovary of the dam. Physiologists, however, regard this as very unlikely. Although at the time that the ovum of a mare is fertilized there are usually other ova almost mature, or approaching maturity, these disappear during gestation. Subsequent offspring arise from successive crops of ova, into whose composition it is most improbable that the earlier spermatozoa could enter. Further, it is known that in the Equidæ the male germinal cells do not live long within the body of the female; they are already disintegrating eight days after insemination, and they probably lose their fertilizing power after three or four days, if not sooner; hence it is not possible for them to remain in the body during the whole of a period of gestation and to fertilize the next succeeding batch of ova.