means of metal identification discs attached to the large clawthe object being to follow migrations-were again unsatisfactory; but such information as it was possible to acquire by this means seems to show that on the West Coast of Scotland (where the major part of the lobster investigations has been carried out) lobsters do not migrate any distance from the local ground. A new method of marking by holes bored or punched on the plates of the tail fin is now being tried: such marks would not be obliterated when the shell is cast. Some observations are also being made on captive lobsters by arrangement with the Manager of the storage pond at Cullipool, and the collection of general data has been extended to the East Coast. A visit was paid to the Orkney lobster fisheries by the Board's expert, who has also visited places from which advice was sought as to the construction of storage ponds intended to obviate the need for sending lobsters to the markets during the hottest summer months.

Mussels and Oysters.-A grant of £2,390 (approximately at the same rate as in the previous year) was recommended by the Commissioners and sanctioned by Your Lordships in aid of an estimated expenditure during 1927-28 of £3,040 on the maintenance of mussel cleansing, and oyster breeding and cleansing operations under the Ministry of Agriculture and Fisheries. Mussel cleansing tanks are now being worked only at Conway, since, as stated in last year's report, the use made by the fishermen of the tanks at Lympstone (Exe Estuary) was insufficient to justify their operation any longer for this purpose. In both cases the fishery had been closed by order of the Ministry of Health, owing to the pollution of the mussel beds by sewage and the consequent danger to the public in consuming mussels taken from them. A process was devised by the scientific staff of the Ministry for freeing the mussels in sterile water from harmful bacteria to an extent which renders them perfectly safe to eat. They are then allowed to be marketed in bags bearing the Ministry's seal. Receipts at Conway during the seven months ended 31st March, 1927, were satisfactory, and a net profit of £200 was realised. This profit will be used to reduce an accumulated loss of £696 on the earlier working of the tanks.

Oyster breeding experiments were continued during the summer in the Conway and Lympstone tanks. On natural grounds spawning is very erratic, and, even when spawn is plentiful, the spat may fail to settle on the bottom after the free-swimming stage in that case the brood is lost. A satisfactory scheme for securing adequate supplies of young oysters would therefore be of great benefit to oyster planters, particularly in view of the recent heavy mortality on the beds. It was found that for three years good collections of spat were obtained from oysters placed in the Conway tanks, and that growth was rapid. In subsequent years the spat fall has varied considerably; the object has therefore been to ascertain the conditions which favour heavy spawning

and subsequent spat settlement in the tanks. The problem is an exceedingly complex one owing to the many factors involved, and the artificial conditions produced in sea water confined in tanks. The experiments, have, however, by a process of gradual elimination of factors, reached a promising stage. At Conway a heavy spat-fall, with a maximum of 200 small oysters per tile, was secured in a tank in which brown sea-weed was placed. It is believed that the spores of this sea-weed provided a suitable food for the spat without rendering the water too alkaline, as was the case when green sea-weed was used. Generally, those engaged on the investigations feel that the aim must be to reproduce, so far as possible, the most favourable natural conditions, while retaining the special advantages which can be provided in artificial tanks, e.g., sheltered conditions, purity of water, plentiful food, suitable temperature and absence of enemies and competitors for food.

At Lympstone the oysters practically did not spawn at all, although in the previous year there had been heavy spawning and an exceptional spatfall. So far it has been impossible to find a reason for this failure to spawn. The intensive study of spawning in oysters now being made from the Plymouth Laboratory may throw light on the perplexing variations found both on natural beds and in the Ministry's breeding tanks.

The experiments at Conway in the cleansing of oysters from sewage pollution were also continued during the winter of 1925-26. So far as can be judged, the scientific investigation is complete, and a satisfactory cleansing process has been evolved. One or two engineering matters remain to be dealt with before the process can be communicated to the oyster industry.

Salmon and Sea Trout.-Application was made by the Fishery Board for Scotland for a grant of £850 to meet the cost in the financial year 1927-28 of investigations on salmon and sea-trout. Of this total £305 was for working up material relating to the life history of salmon known to have been hatched in the years 1917-18, and for continuing the collection and examination of data relating to sea-trout; £445 was in respect of the proposed resumption of the marking of salmon in the sea, an investigation broken off in 1922 for reasons of economy. It was proposed to devote the remaining £100 to re-starting in a different district the experiment begun in the River Oykel in Sutherlandshire, and designed to test under controlled conditions the benefit to a river of stocking it with artificially hatched salmon, and to ascertain whether the offspring of Spring fish returned to the river as Spring fish.

Having regard to the general financial position and the other claims on the limited resources of the Development Fund, the Commissioners felt unable to recommend Your Lordships to sanction more than the grant of £305 for a continuation of the

work on the 1917 and 1918 generations of salmon and on seatrout, though they were advised that the other proposals of the Board were of scientific importance.

As regards the salmon hatched in 1917 and 1918 in the Rivers Dee and Spey, examination of the scales, age, length measurements and other material collected up to the end of 1924 has been completed, and a paper has been prepared on the material obtained, for purposes of comparison, from the River Grimersta in the Island of Lewis. Two points may be mentioned. In the East Coast rivers sampled in this investigation fish appear to return to spawn for the first time in the same class as that in which they first entered the river, though the percentage which returns to spawn a second time is very small. Moreover, the first year of life in the river after hatching is the most important year for growth and weight, and failure to make satisfactory progress in that year is not compensated for in after years.

Over 800 sea-trout were marked during the year under report in the Findhorn, Spey, Ugie, Don and Ythan districts; on their recapture the extent of their migrations and rate of growth will be noted. Scales are also taken from the sea-trout, and the age and growth calculated from them. As has been mentioned in earlier reports, the calculation of the age of the fish from the ring markings on the scales is a specially difficult matter where sea-trout are concerned. The fish feed both in the river and in the estuary, and apparently they often feed during the winter. Periods of slow and rapid growth are therefore not so clearly marked as on the scales of the salmon. Mr. G. Herbert Nall, M.A., F.R.M.S., has given much valuable help to the Board in this work as a volunteer.

In the course of the artificial hatching experiment on the River Oykel (Sutherlandshire) it was found that the burn selected for rearing the salmon fry was unsuitable, owing to clogging of the wire enclosure with vegetable debris. About 60,000 fry were therefore transferred to rearing ponds at Carrol on the south side of Loch Brora. Unfortunately the industrial disputes which occurred immediately after their removal made the supply of food difficult, and it is conjectured that this is the reason why on examination of the ponds in September only some 2,000 fry were found. This experiment aimed, as has been stated, at solving two problems of considerable importance to the salmon fisheries whether Spring fish return as Spring fish, and whether an improvement in the stock of a particular river can be secured by artificial hatching. Salmon hatcheries are, of course, in operation in many parts of the world, but their value has not been demonstrated by critical and scientifically controlled experiment. It is unfortunate that in the present instance the experiment has, owing to a series of misfortunes (floods, drought, and feeding difficulties) been inconclusive, and that financial conditions prevent its repetition for the present.

Plymouth. For the financial year 1927-28 (the third year in a five-year grant period) Your Lordships sanctioned a block grant of £11,390 to the Marine Biological Association in aid of an expenditure of £14,174. There was an increase in estimated expenditure as compared with the previous year of £401. This was partly due to normal salary increments and to wage adjustments, and partly to the taking into full use of the new building, provided by the Association entirely out of private subscriptions. The private income of the Association is also showing a gradual increase, and the use now made of the Laboratory by both British and foreign workers not on the staff is notable. In addition to the Director (Dr. E. J. Allen, F.R.S.) the scientific staff consists of the Head of the Physiological Department (Dr. W. R. G. Atkins, F.R.S)., a Chief Naturalist (Dr. J. H. Orton), two Naturalists, a Hydrographical and Administrative Assistant, a Physiologist, two Assistant Naturalists, the Director's Research Assistant, and two Student Probationers

Millport. The grant period for this station ended on the 31st March, 1927, and, as stated in last year's report, a special SubCommittee was appointed by the Commissioners' Advisory Committee on Fishery Research to visit the Laboratory and report on its claim for further assistance. The Sub-Committee consisted of Sir William Hardy, F.R.S. (Chairman), Dr. Alexander Bowman (Scientific Superintendent, Fishery Board for Scotland), Dr. H. H. Dale, Sec.R.S., and Professor Walter Garstang. In its report, which was adopted by the full Advisory Committee, the Sub-Committee wrote in terms of high praise of the work in progress, the qualifications and enthusiasm of the staff, and of the favourable situation of the Laboratory for marine research. On the advice of their Committee the Commissioners made a promise, subject to the usual safeguards, to recommend to Your Lordships the granting of assistance over a further period of five years, and a block grant of £2,435 in aid of an expenditure of £3,335 was subsequently sanctioned. Provision was made, as suggested by the Advisory Committee, for the addition to the staff of a Student Probationer and a skilled Laboratory Assistant. In view of the difficulties experienced by the Association, owing to the short period which has elapsed since active work on the present scale was commenced after the war, in collecting privately so much as one-third of a gradually increasing expenditure, the requirement that this proportion should be raised was waived as regards the financial year 1927-28; for the same reason an additional grant of £13 was sanctioned in respect of the financial year 1925-26. The scientific staff consists of the Superintendent (Mr. Richard Elmhirst, F.L.S.), a Bio-chemist, an Assistant Naturalist, and a Student Probationer.

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Cullercoats. A block grant of £830 was again recommended for 1927-28, the second year of the present grant-period, to cover the salary of a bio-chemist (Mr. R. Gill, M.Sc.) the wages of a laboratory steward and the expenses of Mr. Gill's research in accordance with an approved programme. The Laboratory also undertakes a considerable amount of directed "fishery investigation for the Ministry of Agriculture and Fisheries. It is a condition of the "free" research grant that not less than £500 per annum be contributed through Armstrong College, Newcastle-upon-Tyne, to which the Laboratory is attached. The full scientific staff consists of Professor Alexander Meek, D.Sc., as Director, a Naturalist, a Bio-chemist, and a Assistant who also acts as Librarian.

Research

Port Erin. The grant to Port Erin (£800) is on the same basis as that to Cullercoats, and is set aside for the salaries of a Bio-chemist and Research Assistant, and the expenses of their research. Your Lordships approved its renewal for 192728, the final year of the five year period for which grants had been conditionally promised. The question of further aid wili therefore come up for consideration during the present financial year.

The Laboratory, though situated in the Isle of Man, is the marine station of the Department of Oceanography, University of Liverpool, and the Professor of Oceanography (Professor James Johnstone, D.Sc.) is its Director. In addition to the Bio-chemist and Research Assistant there is also a Curator, who, besides engaging in research, is responsible for administration. The total expenditure on up-keep is about £1,790. The independent revenue is derived from the University, the Isle of Man Government, subscriptions and donations, and fees for admission to the Aquarium.

Reports on the Work of Institutions.

The work of the Independent Laboratories during the past year is described in reports by their Directors which follow. Their function in the general scheme of research, framed by the Advisory Committee on Fishery Research and aided by the Commissioners, is to build up a body of knowledge of marine biology, chemistry and physiology upon which may be based the investigation by the Fishery Departments of practical fishery problems. The independent laboratories also in some instances take a share in these Departmental researches. marine science, as in all other sciences, it is, of course, often impossible to say whether a particular research is likely to have a practical application, and the only safe method is to plan the attack on primary problems along as wide a front as possible, having regard to the funds available.

In