In the present essay I have endeavoured to bring together the most precise and reliable evidences available as to the recent and present condition of the great trawl and line fisheries of England and Wales. Both these fisheries depend for their success upon the same fundamental conditions, viz. the abundance of fish upon the bed of the sea. They may rightly, therefore, be grouped together under the single head of “bottom fisheries,” in contrast to the fisheries for herrings, mackerel, and pilchards, which are “surface fisheries.” From the nature of the case, even great fluctuations in the annual produce of the latter fisheries scarcely excite surprise, but a fairly constant yield is tacitly expected of the bottom fisheries, when the same apparatus is employed, owing to the greater uniformity in the conditions of life on the sea-floor.

In continuation of the scheme commenced last year for making a detailed survey of the marine fauna in the estuaries on the Devon and Cornish coasts, an examination has been undertaken during the present summer (1901) of the Exe estuary. For this purpose the floating laboratory bot Dawn, which has been generously placed at our disposal and maintained by Mr. J. W. Woodall, was towed to Exmouth and moored in the dock there, where she remained from July to September.

In connection with the work of the Plymouth Laboratory it has been the custom of the Marine Biological Association for several years past to extend its operations during the summer months to the various harbours on the coast of Devon and Cornwall, with a view to making a comparative study of the faunas found in the different localities and of correlating, so far as that may be possible, differences in the character of the fauna with differences in the physical conditions prevailing in each. In former years this has been done by making occasional visits, lasting generally for a few days only, in our small steamer, the Busy Bee. It was found, however, that if investigations of this character were to be satisfactorily carried out some arrangement would have to be made for remaining in one locality for longer periods, and working each harbour in turn in more detail. Mr. J. W. Woodall kindly came to our assistance and purchased the hull of an old cruising yacht, which he caused to be fitted as a small floating laboratory and house-boat, and placed at our disposal for use in connection with the researches. This vessel, the Dawn, which can be towed by our own steamer, has been stationed at Salcombe during the present summer and has proved herself to be very well adapted to the work for which she was intended. We have also to thank Mr. Woodall for defraying the expenses of keeping the Dawn at Salcombe.

Having attempted to investigate the Polychæte fauna of the Plymouth district during those favourable opportunities which have occurred during the past three years, I now put upon record some few notes respecting a small section of this interesting but extremely perplexing group.

The present paper contains an account of experiments made at the Plymouth Laboratory in the summer of 1899 with the object of determining the conditions necessary for the artificial rearing of seafish larvæ through the critical stages of their development. As is well known, the majority of the attempts which have hitherto been made in this direction have proved abortive, and such success as has been obtained has been limited to the survival of a very small proportion of the original stock of fry. There was therefore ample scope for new work upon the subject, especially for experiments based on comparative methods which should aim more particularly to elucidate the habits of fish larvæ under clearly contrasted conditions. In this way only did it appear possible to make further progress in our knowledge of the physiological peculiarities of the delicate fry and of the conditions which are essential to their healthy development in confinement. The successful issue of the present experiments is entirely attributable, I think, to the fact that they were not undertaken until practically undivided attention could be given to them, which enabled me to watch long and closely the habits of individual larvæ under different conditions, and under the guidance of these observations to modify and perfect the simple apparatus employed until the mortality became reduced to reasonable proportions.

Samples of sand were taken, either from the shore immediately above low water of spring tides, or from the bottom in a few inches of water.

With one exception no samples were dredged. The localities were few: Polesands; the north or estuarine shore of the Warren west of Salthouse Lake; the banks of the Salthouse Lake; a low-water stream on the Warren; near Lympstone; and (the dredged sample) within Exmouth Docks.

The investigation of the trawling-grounds in Start Bay, Torbay, and Teignmouth Bay, which had been previously investigated in 1895–8 by Messrs. Stead and Holt, was resumed by the Marine Biological Association in 1901, under authority from the Devon Sea Fisheries Committee.

In the year 1899 I commenced a series of tow-nettings round the coast of Shetland, and established four stations—one south of Sumburgh Head (III.), one west of Papa Stour (IV.), one of the northernmost points of Shetland (V.), and one due east of Bressay (VI.). During 1899 my yacht (the Walwin), a cutter of forty tons, made the round of these stations once a month during October, November, and December; and in 1900 during January, February, March, April, May, and June. During July, 1900, a passage was made across to Thorshaven (and back to Scalloway, Shetland), where stations were established, numbered respectively A1, A2, A3, A4, A5, A6, A7, A8, A9. (See Chart.) During August, 1900, only a short trip to the first two stations in the Faröe Channel was possible. In October, 1900, January, 1901, April, 1901, the stations round Shetland were visited again, and during May, 1901, a further passage was made to Thorshaven and back to Scalloway, visiting the stations previously fixed in the Faröe Channel. This passage was repeated in June, 1901, and again in July, 1901.

The problem of successfully rearing the larvæ of Echinoidea until they had completed their metamorphosis, has been solved by several naturalists. Agassiz was able, for three weeks, to keep plutei alive which he had fished from the sea, at the end of which time they sank to the bottom and became young echini. Bury was able also to rear a few of the plutei of one of the Neapolitan species through the whole of their larval life, and finally Théel has published an account of how he obtained all stages in the development of Echninocyamus pusillus from the result of artificial fertilisation.

There was a time, and that not many years ago, when the fishing-hoats of Brixham sailed round to the east coast of England and joined with the fleets of London, Lowestoft, Yarmouth, and Grimsby in exploiting the fishing-grounds of the North Sea. This carries us back at least two generations, but if one chose to hunt through old records, one might find mention of Brixham and its fishing many centuries ago. The records may even go back to an earlier date than the Armada, but its past history, though of exceptional interest, is of no importance to our present purpose, and we may turn to the doings of the men of Brixham at the present day.

Until the spring of 1899 the true or common octopus (Octopus vulgaris, L.) had been comparatively rare in the neighbourhood of Plymouth during the past ten or twelve years—i.e. since the opening of the Plymouth Laboratory in 1888. Specimens could only be obtained for the aquarium at long intervals, in spite of the tempting inducements offered to fishermen. As much as ten shillings has more than once been given to fishermen for a specimen of this voracious mollusk. On the other hand, the smaller and less powerful octopod known as Eledone cirrosa was almost always obtainable, and the octopus tank in the aquarium was rarely devoid of several specimens.

In the early part of last year (1899) the situation began to change, and we were for the first time able to keep the tank supplied with a number of true octopus, since which date there has been no difficulty in procuring an unlimited number of specimens, either from the professional fishermen or in the ordinary course of our own fishing operations.

We noticed this increase in the abundance of octopus before there was any means of judging whether it was a purely local phenomenon, or was observable over a wider area. The first specimens were brought to us in January, and from May onwards they were obtained in increasing abundance. Early in the same year, however (though I have no exact record of the date), a visitor from the Channel Islands informed me that the increase of octopus in those islands was so great as to have already caused much damage to the shell fisheries there, since the octopus entered the pots of the fishermen, and destroyed the crabs and lobsters which had been caught.

The trawling investigations in the bays were carried out at monthly intervals by means of the Association's steamer Oithona, a small yacht of 69 tons gross tonnage. Only one gap appears in the monthly records for Start Bay (March), and three in those for the other bays. The total number of hauls recorded in the tables is 138, viz. 70 for Start Bay, 30 for Torbay, and 32 for Teignmouth Bay. A few hauls were made on the offshore grounds, but they were not sufficiently numerous to furnish a basis of comparison with the inshore records. Their publication is therefore deferred.

The first part of a lengthened and detailed statistical paper on the structure and seasonal growth of Gadoid and Pleuronectoid scales will shortly be issued from the Marine Laboratory.

The forthcoming paper will show by means of tabulated statistics that scale growth is accelerated during the warmer season of the year; but diminished during the colder season in such a methodic manner as to cause the formation of annual rings. The formation of these annual rings results from the fact that the lines of growth on the scale surface are comparatively widely separated from one another in that portion of the scale formed during the warmer season of the year; but much less widely separated in that part built up during the colder season.

It is a pity that there should be any doubt as to the legitimacy of the generic and specific names of one of the longest Chaetopoda inhabiting Plymouth Sound, and it seems worth while to devote a special note to its synonymy and identification.

On the invitation of the Swedish Government an International Conference met at Stockholm, in June, 1899, for the purpose of formulating a scheme for a combined investigation of the Northern Atlantic, the North Sea, and the Baltic in the interests of the sea-fisheries.

“The spawning periods of the food-fishes have been fully ascertained for the east coast of Scotland by Dr. Fulton and other Scottish workers, and the present occasion afforded a good opportunity of determining the spawning time of the plaice on the south-west coast of England. Mr. Cunningham's work, published in previous numbers of this Journal, and in more compendious form in his book on Marketable Marine Fishes, covers the whole field of fishery investigation, and forms therefore an excellent basis for more definite and detailed research. The spawning period of the plaice, for example, is given as January, February, and March for the North Sea and English Channel, and in a general way this is quite correct, but it is somewhat vague. The plaice of the Bristol Channel also spawn during the months mentioned, but on the whole later than those of the English Channel. It is evident, therefore, that we must ascertain the periods at which most plaice are spawning or have spawned, in other words the maximum spawning period as it is generally called. The difficulties in the way of ascertaining this accurately arise from the facts that all fish do not spawn exactly at the same time, and that one fish may take two or more weeks in getting rid of all its spawn. We cannot, therefore, delimit the maximum spawning period to less than two to three weeks, and if we allow for fluctuations in different years, one month is the nearest approximation we can make.

Sycon compressum is one of the long-recognised sponges, that stand refreshingly conspicuous in a group made difficult with doubtful definitions. The unique dermal spicules, and the striking outward form, divide it from other species in a way quite different from that in which Sycon raphanus is divided from S. villosum or Renicra cinerea from Reniera permollis.