bluuebunny/crossref_metadata_2025 huggingface dataset:
Variations in the activity of the thyroid gland of the cod,Gadus callariasL., in relation to its migrations in the Barents Sea II. The ‘dummy of run’ of the immature fish
Authors: Woodhead A. D.
Published: May 2009

Describing the migrations and movements of the cod,Gadus callariasL., in the Barents Sea, Trout (1957) suggested that the immature fish carry out a false spawning migration. ‘The pattern of migration of the immatures is basically similar to that of the matures…with increasing age, the immatures’ southerly winter migration approached in length that of the mature cod, as if, in the years immediately prior to maturity they were making a “dummy run” towards the spawning ground.' The seasonal migrations of both the adult and immature cod have been related to changes in the activity of the thyroid gland in this fish (Woodhead, 1959). During the spring of 1956 and 1957, collections of thyroid glands from immature cod were made at stations from Bear Island to the Norwegian coast. It was hoped that a study of these glands might demonstrate further the relationship of the activity of the thyroid gland to the migration of the fish.
Sea surface temperatures at Millport
Authors: Barnes H.
Published: May 2009

Sea surface temperatures have been taken daily at Keppel Pier, Millport (55° 44‘ 55“ N. lat.; 4° 54’ 20” W. long.), for the past 10 years (1949–58), the data being included in returns to the Meteorological Office. The records are not given in their standard publication and they are, therefore, presented here to supplement those of Cooper (1958) for inshore waters at Plymouth some 400 miles farther to the south. For some years the samples were drawn in a specially constructed container fitted with a Fahrenheit thermometer which was read to the nearest whole degree; more recently the bucket method has been used, and a centigrade thermometer graduated in degrees and read to an estimated tenth of a degree. The two methods were checked against each other before the change was made and the results found to be consistent. All readings were taken at 09.00 h G.M.T., irrespective of the state of the tide. The results are shown in Table 1.
The Food of Young Clupeoids
Authors: Lebour Marie V.
Published: May 2009

Whilst investigating the food of young fishes in general (Lebour, 1918–1919–1920) some thousands of young Clupeoids were examined, with the result that by far the larger proportion of post-larvæ were found to be empty. Here and there, however, food was present, and by bringing these records of 1917 to 1919 together, with some from 1920 and 1921, we have a good idea of the food of our three common Clupeoids—Herring, Sprat and Pilchard—in their young stages.

A probable reason for this apparent absence of food in the transparent stages is that the food must be very quickly digested on account of its being so conspicuous; thus it is probably taken only at long intervals and rapidly got rid of. It would follow that under these circumstances we should only occasionally catch the fish when food was inside it.

The observations on the food of the young Herring are perhaps the most interesting of the three on account of the fact that it eats solid food some time before the yolk sac is absorbed, the mouth being open when the fish is hatched, whereas the Sprat and Pilchard, being much less advanced, are only able to feed on outside food much nearer the time when the yolk sac disappears. Unfortunately we have no records of Pilchard food in the very young stages (under 12 mm.), green food remains being found in those of the Sprat before the yolk sac has completely disappeared.
A Contribution to Our Knowledge of the Life-Histories of the Dogfishes Landed at Plymouth
Authors: Ford E.
Published: May 2009

In view of the fact that dogfishes are now of undoubted importance as marketable food fishes, it is necessary that the life-history of each of the species concerned should receive closer attention than hitherto. The present publication is the result of an endeavour to gain a personal working knowledge of the general life-history of the species which are landed at Plymouth. In carrying out a scheme of work of this kind it is certain that many of the observations made will have already been carried out previously by other workers, but, nevertheless, the results obtained are of value, not only in regard to the degree of confirmation which they afford, but also in the building up of an account of the life-history under the local conditions. In some instances, too, it will be seen that the actual numeric results in themselves are of little statistical value, but they yield very interesting suggestions which may be confirmed or disproved by a repetition of the experiments on a larger scale. I express my thanks to the fish-buyers at Plymouth fish-market, particularly Mr. J. Vanstone, for their kindness in allowing me to handle their fish before dispatch, and for their assistance in obtaining a regular supply of material for many months.
Seasonal and Environmental Effects on the Lipid Composition ofNeomysis Integer
Authors: Morris Robert J.
Published: May 2009

During the last 3 years a survey of marine lipids has been in progress in this laboratory. Several classes of marine animals have been analysed for their fatty-acid composition. These results have shown a considerable species variation but no estimate could be made of the effect of season and environment. It was therefore decided to choose an inshore animal, which could be readily collected, and to examine its lipid composition with regard to seasonal and environmental changes.

The brackish-water, partly planktonic mysid,Neomysis integer(Leach), was selected. This species has already been the subject of much biochemical study (Raymont, Austin & Linford, 1964, 1966, 1968; Linford, 1965), in which the three major fractions protein, lipid and carbohydrate were examined. The lipid weight was found to be low in comparison with the protein content. Also, significant decreases in the lipid were found in November, January and March. It was concluded thatN. integerstored little lipid as a metabolic energy reserve, and as the carbohydrate was low, protein may be catabolized. Only one sample analysis for fatty-acid composition was reported.

The marine speciesNeomysis nakazaviaihas been investigated by Yamada (1961), but unfortunately an ether extract was taken from sun-dried material and so the results are not comparable with the present work onNeomysis integer.

In the present study the saponifiable fraction of the lipid is examined in more detail in an attempt to establish the relative importance of the factors of season, temperature and salinity upon the fatty-acid composition.
The Distribution of the Major and Some Minor Elements in Marine Animals Part II. Molluscs
Authors: Segar D. A. , Collins J. D. , Riley J. P.
Published: May 2009

INTRODUCTION

It has been known for a long time that the soft tissues of molluscs contain relatively high concentrations of certain trace elements—mainly transition metals (see, for example, Vinogradov, 1953; Bowen, 1966). However, with the exception of the work by Brooks & Rumsby (1965) on the occurrence of 12 elements in 3 New Zealand bivalves, most of the investigations have concerned the distribution of only one or two elements. This has prevented a study being made of possible interelement correlations. The present work was carried out in an endeavour to determine the usual levels of several minor elements in a variety of molluscs from the Irish Sea and to seek evidence for such correlations.
On the Scabbard Fish Aphanopus Carbo
Authors: Bone Quentin
Published: May 2009

INTRODUCTION

The black scabbard fish, Aphanopus carbo Lowe, is an elongate mid-water trichiurid, which is caught commercially off Madeira, and has been recorded, though infrequently, from British waters (Tucker & Palmer, 1949; Tucker, 1956). Twelve specimens were caught during a recent cruise of R.V. ‘Sarsia’ in the Biscay area (Forster, 1970), and this note reports observations on their behaviour, histology and anatomy, which suggest that these fish are highly specialized for a particular method of catching prey.
Studies on luminescence. Attraction of animals to a weak light
Authors: Nicol J. A. C.
Published: May 2009

In order to evaluate the biological significance of luminescence, it is desirable to know how weak light affects the behaviour of marine animals, and what intensities they can see. Much information is available concerning the attractive power of bright lights, and light directed movements (see Verheijen, 1958, for example), but little for weak point sources. Weak coloured lights have been used by Baylor & Smith (1953) to trap freshwater arthropods.
On the sexual biology of Pandalus borealis(Crustacea decapoda) II. The termination of the male phase
Authors: Carlisle D. B.
Published: May 2009

Pandalus borealis Krøyer is a protandric hermaphrodite. In some populations, e.g. that found off the Northumberland coast, the hermaphroditism is partial (Allen, 1959). That is to say only certain individuals undergo sex reversal, while others are primary females, never going through a male phase; all the males undergo sex reversal. In the terminology proposed by Carlisle (1959 a) such populations exhibit partial obligatory protandric hermaphroditism. By contrast, the population of the Gullmarf jord, Sweden, which I have been investigating, appears to exhibit full obligatory protandric hermaphroditism: the population contains no primary females; all the females have passed through a male phase. The data presented in this paper have no bearing, therefore, on the factors regulating the production of primary females, since I have never encountered one.
A Hopper for use when sieving bottom samples at sea
Authors: Holme N. A.
Published: May 2009

When large quantities of bottom soil are brought up by the dredge or grab, the problem of sieving the material within a reasonable time presents itself. The usual practice is to wash the soil through a sieve or series of sieves, the finest being of the order of 1–2 mm aperture, according to the nature of the soil or the size of the animals to be collected. It is usually necessary to agitate the soil either by spraying with a hose or by shaking the sieve in a bath of water, in order that finer particles may pass through the sieve. Many of the more delicate animals are damaged by these methods, and Spooner & Moore (1940), working on the Tamar estuary, found it necessary to mix the mud carefully by hand with water to make a ‘soup’ before it could be sieved without damage to the fauna. For work at sea Hartman (1955) describes a machine by which sieving was accomplished with the aid of water sprays and mechanical agitation of the sieves with power provided by an electric motor.
The influence of temperature on the reproduction and moulting ofLepas anatiferaL. under laboratory conditions
Authors: Patel Bhupendra
Published: May 2009

Lepas anatiferaL. is generally found on floating objects in tropical and sub-tropical oceanic waters, where sea temperatures exceed 18–200C.
A note on some physical conditions for cultivating Oxyrrhis marina
Authors: Droop M. R.
Published: May 2009

This note concerns a series of experiments to determine the best conditions of salinity, temperature and pH for cultivating the euryhaline phagotrophic dinoflagellate Oxyrrhis marina Dujardin.

The strain of Oxyrrhis employed was isolated from a brackish pool at Tvarminne, Finland (Droop, 1953a, b). The culture medium for the experiments contained soil extract and an artificial sea water, SW 1 (NaCl, MgCl26H2O, KCl, and CaSO42H2O in the proportions by weight 15:2.5:0.4:0.5), and for food a small quantity of the yeast Saccharomyces exiguus was administered daily from an agar culture with a wire loop.
Water-soluble factors in the nutrition ofOxyrrhis marina
Authors: Droop M. R.
Published: May 2009

Oxyrrhis marinaDujardin is a non-photosynthetic dinoflagellate whose obvious mode of nutrition is phagotrophy. The method of feeding was described by Barker (1935). It is an extremely euryhaline and hardy organism and is apparently very successful in brackish habitats such as supralittoral rock pools and ditches (Droop, 1953 a). Owing to the ease with which it can be cultivatedOxyrrhisis a choice for the initial study of phagotrophy among the predominantly plant-like Dinoflagellata.
The biology of the prawn, Palaemon (=Leander) serratus (Pennant)
Authors: Forster G. R.
Published: May 2009

In a recent paper Cole (1958) has offered a new interpretation of the results obtained in 1949 and 1950 during my investigations of the biology of prawns. The present paper is the outcome of a re-examination of these results and of further prawn measurements which were continued on a small scale until 1955. The later investigations consisted of an annual survey of the prawns, particularly the O-group, caught from the rocks on the south side of the R.A.F. Station, Mount Batten, usually during the first low spring tides every October. The total number of prawns measured in the whole period was over 8,600.
Further Observations on Marine Ciliates Living in the Laboratory Tanks at Plymouth.
Authors: De Morgan W
Published: May 2009

Alwaysto be found in Drake's Island Tank.* Very abundant during the summer, but diminishing innumber during the winter months. It has been described by O. MÜller (22), Ehrenberg (6), Stein (31), Dujardin (5), Claparede and Lachmann (3), under various names, but their descriptions may be regarded as only of historic interest. The later observations of Gruber (13), Cohn (4), and Entz (8) aremore detailed, and Lebedew (17) has given the fullest account of the animal. Kent (16), Biitschli (1), and SchewiakofE (27) have only short notices.
The Nitrite Content of Sea-Water.
Authors: Orr A. P.
Published: May 2009

1. The method of water sample preservation used by Gad-Andresen is not suitable for nitrite or nitrate estimation.

2. Using Buch's method it has been shown that the variation in nitrite during the summer is from less than 0-001 mg. to about 0-01 mg. per litre and that the deeper water layers have more than the surface layers.
Notes on the Preservation of Fishing Nets by means of Copper Soaps.
Authors: Atkins W. R. G.
Published: May 2009

The use of a mixture of copper soap, 5 or 10 per cent, with 1 per cent mineral oil, dissolved in petrol or benzol, increases the life of silk plankton nets by about four or five hundred per cent, and roughly doubles that of a hemp net for a single treatment. The beneficial effects last far longer than does the green colour. Re-treatment at suitable intervals is recommended.

The use of 5 or 10 per cent of resin * with an equal percentage of the soap improves its adherence to the fabric, as does also the addition of tar or anti-fouling paint. For silk nets, to avoid clogging, only one-half per cent of resin should be used with 5 per cent of soap.

A liquid soap mixture, which may be used with paraffin oil, can be obtained by adding one pound of resin to one pound of melted copper soap, and then dissolving in one and a half pounds of carbon tetrachloride. When wanted, this is used to make up a paraffin oil soap solution of the desired concentration, but adherence is less than with petrol.
Notes on Experiments on the Early Developmental Stages of the Portuguese, American and English Native Oysters, with Special Reference to the Effect of Varying Salinity.
Authors: Amemiya Ikusaku
Published: May 2009

1. The period of time which the oyster larva requires to attain its respective developmental stages was measured and recorded in 0. virginica and 0. angulata.

2. The development in various concentrations of salinity was studied in the three species, 0. virginica, 0. angulata, and 0. edulis.

3. In optimum salinity, all the impregnated eggs undergo segmentation and further development; the rate of development is uniform and its progress speedy.
On Lunar Periodicity in Spawning of normally grown Falmouth Oysters (O. edulis) in 1925, with a comparison of the spawning capacity of normally grown and dumpy Oysters.
Authors: Orton J. H.
Published: May 2009

During 1925 dumpy oysters spawned in a high proportion on the Fal beds, and although not such heavy breeders as normal oysters, they are undoubtedly valuable in forming a stable spawning stock for replenishing the beds in the future. Nearly every normal and dumpy oyster above a size of 2 to 2\ inches produced at least one batch of spawn in 1925. Since dumps increase in proportion on the beds as over-fishing occurs, they form a natural breeding reserve for repopiilating the beds in favourable years, as there is no adequate reason to suppose that the larvae of dumps are unhealthy. Weekly samples of oysters examined closely during the summer of 1925 for the percentage of spawning females and ripe but unspawned females show
Medusæ as Hosts for Larval Trematodes
Authors: Lebour Marie V.
Published: May 2009

The larval form (late cercaria stage) of Pharyngora bacillaris (Molin) has been recorded by Nicoll (1910) from Plymouth as occurring free in the coarse-meshed tow-nettings in August. The adult is a common parasite of the mackerel, and the above is the only record of its larval stage.

Whilst examining tow-nettings at Plymouth in 1915 it was found that certain medusæ were at times abundantly infected with a trematode which proved to be the larval form of Pharyngora bacillaris. As it also occurred free, although almost certainly having originally come from the medusæ, it is obviously the form recorded by Nicoll, who expected the host to be a crustacean and unsuccessfully examined copepods in order to find it.

The medusæ found to contain the trematode were Obelia sp., Cosmetira pilosella, and Turris pileata. Cosmetira pilosella was the commonest host in the early summer when Pharyngora was most abundant, but in the later summer Obelia was found to contain it frequently, Cosmetira not occurring at those times in the tow-nettings. Phialidium hemisphericum was also a host in the later summer and autumn. Even in December it still occurred, though very rarely. A ctenophore may also serve as host for this trematode, as it is occasionally found clinging to the inside of the stomach of Pleurobrachia pileus.

The parasite is generally to be found clinging to the manubrium or stomach wall of its host, but sometimes it occurs underneath the umbrella wall, so that it looks as if it were on the top, the wall being so transparent; on further examination, however, it is seen to be underneath.
An Account of the Researches on Races of Herrings Carried out by the Marine Biological Association at Plymouth, 1914–15
Authors: Orton J. H.
Published: May 2009

[The following Tables record the measurement and enumeration of a number of characters in certain samples of Herrings taken in the neighbourhood of Plymouth. The work was carried out as part of a general scheme for studying the question of the existence of local races of herrings around the British Coasts, which was organised by the Board of Agriculture and Fisheries. In consequence of the war there is no immediate prospect of the figures being analysed and compared with similar figures relating to fish obtained in other localities. It has therefore been thought advisable to place them on record as they stand, so that they may be available for other workers at any time. The short explanatory statement of the methods employed was prepared by Dr. Orton, who had charge of most of the work, to accompany the figures when they were sent to the Board of Agriculture and Fisheries, and was not written by him with a view to publication. The drawings have been made by Mrs. Sexton.—E. J. Allen.]
On the Amount of Phosphoric Acid in the Sea-Water off Plymouth Sound
Authors: Matthews Donald J.
Published: May 2009

1. Phosphoric acid in sea-water may be determined with an accuracy of about 0-003 mg. per litre by concentration with iron and colorimetric examination.

2. If the sea-water be previously oxidised by potassium permanganate the amount found is considerably increased.

3. From September, 1915, to February, 1916, the average amount of phosphoric acid in water collected half a mile outside Plymouth Break-water was 0-044 ing. per litre ; this showed signs of an increase when the supply of land-water rose after rain. The figures are much lower than those found by Raben for the Baltic and North Sea.

4. The amounts found by another method during the previous spring and summer are higher, but the figures cannot be considered quite trustworthy.
Order Pteromedusae
Authors: Kramp K. L.
Published: May 2009

Trachyline medusae whose body is divisible into aboral and oral halves, separated by a line of tissue lying in the bottom of a constriction, this tissue representing the margin of the umbrella which is divided into four flaps acting as swimming lappets; the subumbrellar part of the body is highly reduced and consists of only the manubrium and the tissues on the adoral surfaces of the lappets. Without tentacles, but with statocysts on the oral sides of the lappets; statoliths endodermal. Gonads of ectodermal origin; development direct.
On the Vertical Mixing of Sea-Water and its Importance for the Algal Plankton
Authors: Atkins W. R. G.
Published: May 2009

1. Measurements of hydrogen ion concentration, of phosphate concentration, and of temperature all show at certain seasons a well-marked gradient from surface to bottom. The upper 10–20 metres is more alkaline, notably depleted of phosphates and warmer.

2. Settled summer weather and deep water, free from irregularities of the bottom, favour the formation of such a gradient. Its breaking up is occasioned by wave action and the cooling of the surface water in autumn.

3. Thermal stratification in the English Channel arises at each station, and is not due to the inflow of warm over colder water.
The Euphausiidæ in the Neighbourhood of Plymouth and their Importance as Herring Food
Authors: Lebour Marie V.
Published: May 2009

An investigation into the euphausiids in the Plymouth waters was undertaken on account of the fact that on examining adult Herring for food it was found thatNyctiphanes Couchii(Bell) was of great importance, and occurred in enormous numbers in a large proportion of the Herring caught in the earlier half of the period of the Herring fishery.
Malignant Tumours in Fishes
Authors: Johnstone Jas
Published: May 2009

This paper contains a general account of about forty examples of tumours, mostly “malignant,” found in eighteen species of fishes, all of them marine except two, a Stickleback and a Gold-fish. In all these cases the affection was a very obvious one, attracting immediate attention from the fishermen who caught the specimens, or leading to condemnation of the fish by market inspectors. In some cases the appearance presented by the fish was grotesque, or repulsive in the extreme. I give a list of the specimens dealt with on p. 447–8: all these represent “cancerous” affections. Many other diseased fishes, obtained in the same ways, have been seen and examined. Malformations of development, or growth; large healing scars due to wounds; repulsive ulcers of unknown origin; parasitic tumours and two cases of undoubted piscine tuberculosis (in Cod) have also been examined. Here, however, I refer only to tumours which exhibit the character of malignancy.
The Food of Calanus Finmarchicus during 1923
Authors: Marshall Sheina
Published: May 2009

In view of the importance of Calanus as a food for fish, and especially for the Herring, its food and feeding habits have been kept under examination throughout the course of the year.
On Leptonereis glauca Clpde., and the Genus Leptonereis Kinberg
Authors: Ramsay L. N. G.
Published: May 2009

In February of this year Mr. J. H. Orton collected a number of small nereids on the piles of a wharf at the Great Western Docks at Millbay, Plymouth. These he kindly handed over to me for identification, and, along with other material collected at Plymouth in March, they form the basis of this paper.

These nereids proved to be none other than the little-known Leptonereis glauca of Claparède, of which the only specimen hitherto recorded from the shores of this country was found by Major E. V. Elwes at Oddicombe (8, p. 351) some years ago.
OnAlcyonium pulmonis instar lobatumEllis
Authors: Hartmeyer R.
Published: May 2009

In the year 1755 Ellis described in his “Natural History of the Corallines,” as “Alcyonium pulmonis instar lobatum,” a “sea production” from Whitstable, which the fishermen there had brought to him under the name of “Sea-Fig.” As regards the systematic position of this form, he expresses himself only in so far as to place it with the Alcyonians, a group in which were united at that time, along with true species of Alcyonium, Ascidians, Hydroids, Sponges and even Algæ. As a doubtful synonym of his species Ellis put forward thePulmo marinusof Rondelet (1555), which however has nothing whatever to do with it and indeed cannot be certainly determined. During the following years, Ellis' work was translated into several languages. A Dutch and a French translation, both dating from the year 1756, are known to me, the former by Tak, the latter by Allamand. There is also a German translation by Krüniz dated 1767.
The Vertical Distribution of Marine Macroplankton IV. The Apparent Importance of Light Intensity as a Controlling Factor in the Behaviour of Certain Species in the Plymouth Area.
Authors: Russell F. S.
Published: May 2009

Results of collections with the ring-trawl to obtain evidence on the vertical distribution of plankton animals in daylight at different times of the year and at night are given.

The vertical distribution of Calanus finmarchicus and Cosmelira pilosella is discussed in relation to the distribution of light intensity in the sea.

Results show that light intensity is apparently the external factor of greatest importance in determining the vertical distribution of these plankton animals in this region.

Many more observations at sea correlated with simultaneous records of light intensity at different depths are required, together with laboratory experiments on the effects of various factors on the behaviour of plankton animals kept under different conditions of light intensity.
The Precipitation of Calcium and Magnesium from Sea Water
Authors: Irving Laurence
Published: May 2009

Apparently calcium carbonate is precipitated in certain parts of the ocean by processes which are inorganic in so far as that the calcium does not first form a true constituent of organisms (Clarke, 1920, p. 128). The conditions governing solubility of calcium in sea-water have been reviewed by Johnston and Williamson (1916) with the conclusion that surface layers of the ocean are approximately saturated, and that slight natural changes, particularly in carbon dioxide tension, might suffice to cause precipitation.
The Phosphate Content of Sea Water in relation to the Growth of the Algal Plankton. Part III.
Authors: Atkins W. R. G.
Published: May 2009

A comparison of the years 1923, 1924 and 1925 as regards the phosphate content of the water at Station El in the English Channel has shown that the vernal diminution was earliest in the year 1924, and latest in 1923, the extreme difference being approximately two months. These differences stand in direct relation to the spring sunshine, that of 1924 for the daily average of the 9th to 12th weeks inclusive being 2-3 hours in excess of the normal, 1923 being 0-1 hr. in deficit and 1925 being 0-6 hr. in excess. Since the phosphate diminution is proportional to the increase in phytoplankton the year 1924 must have been exceptionally early in this respect.

The year 1925 was in general similar to the other two in having a summer phosphate minimum and a winter maximum; but it was noticeable for marked periods of regeneration of phosphate, followed by utilization, within the main cycle.

The maximum value at El was 40 mg. per m3 of phosphate as P2O5, the minimum 5-1 mg. for thewhole water column, 0-70 metres.

Much additional evidence has been found to show that the deep water of the ocean is a reservoir of phosphate, containing 50-80 mg. per m3, or more.

The water of the North Sea was markedly richer in phosphate in the spring of 1925 than in that of 1924, as was also the water around the Faroe-Shetland Channel in July, 1925, as compared with the previous July. A causal connection may be sought.

In tropical waters the intense light normally results in the utilization of all phosphate down to at least 50 metres, and the winter cooling never suffices to effect mixing with the deeper water. At about 38N. latitude the water may be expected to be isothermal in winter to a depth of 350-400 metres, and further north the isothermal column has its base deeper down; accordingly the seasonal phosphate cycle must become more pronounced.
The Moulting Stages of the Pea-Crab (Pinnotheres pisum)
Authors: Atkins D.
Published: May 2009

Pinnotheres pisum is a small crab with a carapace between about 2−1 and 18 mm. wide. The females are commonly found parasitic in the mussel, Mytilus edulis, though they have been recorded from other bivalves. The males are free-swimming and are comparatively rarely found in mussels. These small crabs are never abundant, and not more than one female has ever been found in a mussel.
Abnormal Vertebræ in Herrings
Authors: Ford E. , Bull H. O.
Published: May 2009

An important part of recent investigations on herrings at Plymouth has been the collection of statistical data on the number of vertebræ, and when this report was written a total of 6869 fishes had already been examined with regard to this character. In the case of each of 105 fishes, however, the true number of vertebræ could not be stated with confidence, owing to marked irregularities in one or more vertebræ. These abnormal specimens are of more than passing interest. The abnormalities themselves are such that it would be well worth while to make a careful morphological study of “ fresh ” specimens to determine the extent to which nerves and muscles are affected. The determination of the distribution of abnormalities along the vertebral column suggests a possible explanation of the way in which they may have arisen. Moreover, there remains the question as to how the abnormal vertebræ should be counted when endeavouring to ascertain the true total number of vertebræ for statistical or genetic purposes. In the paragraphs which follow, the 105 cases of abnormality are described and their significance both in numbers and position discussed, but it should be remembered that all observations and measurements were made on dried skeletons, which had been prepared by boiling and cleaning.
On the Growth of some Lamellibranchs in Relation to the Food-supply of Fishes.
Authors: Ford E.
Published: May 2009

During a study of the fauna of the level sea-bottom off Plymouth on which a report has already appeared in this Journal (Ford, 1923), the samples taken in the Petersen bottom-sampler and in the conical dredge were preserved in alcohol and retained. A subsequent re-examination of the accumulated material has provided information on the growth of a number of lamellibranchs, which forms the subject matter of the present paper. As the samples were collected according to a programme arranged expressly to determine the animal communities represented, it was not to be expected that they would yield complete data on the growth of a particular species, but the results are interesting and useful when considered in their relation to the food supply of our food-fishes. I must again acknowledge my indebtedness to Mr. R. Winckworth of Brighton for his continued assistance in identification and measurement of specimens. Such expert confirmation of identification was naturally desirable’ in dealing with the growth of species from the earliest stages. Throughout the paper the term “length” is adopted, meaning the greatest antero-posterior dimension of the shell. This term was used by Weymouth (1923) who gave a figure on page 20 which shows clearly the measurement to which the term is applied. I have also used “length” as a measure of growth-rings on the surface of shells. In Fig. 7 on Plate III, I2 is the length of the second ring on a shell of Spisula solida. Thirty-three genera of lamellibranchs are represented in the material of which all but nine appear among the records compiled by Todd (1907) and Blegvad (1917) of the contents of the stomachs of fishes which include dab, flounder, long-rough dab, plaice, sole, cod, haddock, whiting, cat-fish, viviparous blenny, fresh-water eel, herring and mackerel.
On the Thermal Stratification of Sea Water and its Importance for the Algal Plankton
Authors: Atkins W. R. G.
Published: May 2009

In a previous paper (1924) the writer considered the factors which bring about the mixing of surface water, warmed by the sun, with the cooler water below. Observations were cited to show that in the English Channel, between May and September, a warm surface layer may exist, which differs from the deeper water in being more alkaline and poorer in phosphates; both these differences are due to the activity of the phyto-plankton. The reduction in phosphate proceeds in the upper well-illuminated layer till none is left. No further increase in phytoplankton is then possible till phosphate is set free by decomposition or supplied by mixing with the deeper water. The phenomena of thermal stratification are consequently of great importance in the study of the phyto-plankton.
Notes On Euphausiids
Authors: Hickling C. F.
Published: May 2009

(a) Vertical Migration

The material for this paper was obtained in two voyages on the Milford steam trawler Macaw, and I owe all thanks to Capt: Rumble, and to the crew, not only for much practical help, but for a pleasant time. Capt. Rumble's knowledge of the area worked, based on 30 years' experience, can only be compared with a farmer's knowledge of his own acres, and he has been responsible for determining the position of each haul.
On the Culture of the Plankton Diatom Thalassiosira grauida Cleve, in Artificial Sea-water
Authors: Allen E. J.
Published: May 2009

1. Attempts to obtain good cultures of Thalassiosira gravida in a purely artificial medium, made by dissolving in doubly distilled water Kahlbaum's pure chemicals in the proportions in which the salts occur in sea-water, adding nitrates, phosphates and iron according to Miquel's method and sterilizing the medium, have not succeeded.

If, however, a small percentage of natural sea-water (less than 1 per cent will produce a result) be added to the artificial medium and the whole sterilized excellent cultures are obtained, which are often better than any which have been got when natural sea-water forms the foundation of the culture medium.

The result appears to be due to some specific substance present in minute quantity in the natural sea-water which is essential to the vigorous growth of the diatoms. The nature of this substance it has not been possible to determine, but some evidence seems to suggest that it is a somewhat stable organic compound.

Provided the 1 per cent of natural sea-water is added, the various constituents of the artificial sea-water forming the basis of the culture medium can be varied in amount within wide limits. The salinity of the medium can also be considerably altered without serious detriment to the cultures.

The experiments recorded are of interest as furnishing another instance of the importance in food substances of minute traces of particular chemical compounds. They may also eventually throw light upon the nature of the conditions in the sea which are specially favourable to the production of plant life and therefore also of the animal life which that plant life sustains.
A Study of the Restitution Masses formed by the Dissociated Cells of the Hydroids Antennularia Ramosa and A. Antennina
Authors: De Morgan W. , Drew late G. Harold
Published: May 2009

The Hydroids experimented on were Antennularia ramosa, and A. antennina.

These were cut in pieces and pressed through bolting silk, with the result that isolated cells and small cell aggregates were obtained, which soon aggregated together to form compact masses.

These restitution masses secreted a perisarc within from 12 to 18 hours.

Various changes in shape, and general retraction of the mass away from the perisarc occurred later, but even up to 60 days there was no sign of the regeneration of the hydranths.

The restitution masses consisted of ectoderm and endoderm cells, and in addition such structures as nematocysts, ova, and brokendown cells, all of which were subsequently absorbed and played no part in the future development. The ectoderm cells were relatively little damaged, and were embedded in a plasmodial mass formed by the endoderm cells.

A definite layer of ectoderm cells is formed on the surface, and thesecells secrete the perisarc.

Gradual aggregation and segregation of the endoderm cells from the plasmodial mass takes place ; and they form very definite tubules similar in structure to the coenosarcal tubules continuous with the enteric cavities of the normal hydranths. These tubules are embedded in a mass of ectoderm cells, they are convoluted and ramify in all directions. Many granules develop in the cytoplasm of these cells, and after about a month many of them have degenerated.

The ectodermal cells show no signs of degeneration, and the masses containing them have been kept alive for 60 days at the time of writing.

In none of the experiments was there any sign of the occurrence ofcell division
The Trematode Parasites of Fishes from the English Channel
Authors: Nicoll William
Published: May 2009

In continuation of my researches on the entozoa of British marine fishes I spent two months (August and September, 1909) at the Plymouth Marine Biological Station. By the courtesy of the Government Grant Committee of the Royal Society, a table was placed at my disposal and all expenses in connection with the investigation were defrayed.
The breeding ofBalanus porcatus(Da Costa) in the Irish Sea
Authors: Crisp D. J.
Published: May 2009

Balanus porcatus(da Costa) is a widely distributed northern species, being found in the Arctic Ocean as far as 80° N., and in the northernmost extensions of the Atlantic and Pacific Oceans. Its southern limits are closely related to water temperatures. Whereas on the east coast of America, where the Labrador current flows southward, it extends to Long Island (lat. 40° N., see Pilsbury, 1916), on the west European coast it scarcely penetrates the English Channel (lat. 51° N.). It is found in some abundance however in the North Sea, the Skagerrak and Kattegat (Krüger, 1927), the Irish Sea, and off the west coast of Scotland and Ireland. The present survey is probably representative of its breeding habits in regions near the southern limits of its range.
The suspended matter in sea water and its seasonal changes as affecting the visual range of the Secchi disc
Authors: Atkins W. R. G. , Jenkins Pamela G. , Warren F. J.
Published: May 2009

In a previous paper (Armstrong & Atkins, 1950), 201. samples from International Hydrographic Station England No. 1 (EI), about 10 miles south-west of the Eddystone in the English Channel, were filtered through collodion membranes of 1.09μ average pore diameter (A.P.D.).

Between June 1948 and November 1949 the residue from these surface samples, when dried and ignited, amounted to 0.45–2.77 g/m3(or parts per million). These deposits consisted of 55–17 % silica, 28–3 % ferric oxide, 20 to under 1 % of alumina, and 70 (or, excluding one high value, 29) to 9 % calcium carbonate. A few determinations of insoluble organic matter gave to 1.15–1.77 p.p.m. when dried at 100° C. Pettersson (1934b), using the glass niters of Schott (Jena), found 1.4 p.p.m. for the total organic and inorganic matter similarly dried, from surface water in the Gullmar Fjord during the spring outburst.
R.V. Sarsia: a brief description of the Marine Biological Association's new research vessel
Authors: Steven G. A. , Hoodless C. A. , Harrison R. S. , Warren F. J.
Published: May 2009

From 1922 until the outbreak of the 1939–45 war, the Association's Laboratory at Plymouth was well served by the research vessel Salpa—a converted Lowestoft steam drifter having an overall length of about 95 ft. In 1939 Salpa was taken over by the Admiralty for naval duties and was not put back into service by the Association on her release after hostilities ended. Her place was taken by a 90 ft. motor fishing vessel on charter from the Admiralty and named Sabella. This vessel was only partially converted for research work and was handed back to her owners when Sarsia came into service at the end of 1953
The ciliary feeding mechanism of the cyphonautes larva [Polyzoa Ectoprocta]
Authors: Atkins D.
Published: May 2009

The cyphonautes larva found in certain ectoproct Polyzoa is considered to be most probably a primitive larval form, which has been lost in viviparous species, the larvae of which are degenerate in varying degree and settle within a short time. The cyphonautes is truly planktonic and has a free swimming Life of some length—of 2 months according to Marcus (1940, p. 334)—and unlike the other known larvae of the group, has a functional alimentary canal. It obtains its food by maintaining a continuous current of water through the mantle cavity or vestibule, its ciliary mechanism being organized on a plan somewhat resembling that of bivalve molluscs, with an inhalant and an exhalant chamber with interposed ciliary ridges bearing current-producing and food-conveying cilia. As in lamellibranchs the organ creating the water and food currents is separated by a considerable interval from the mouth. In lamellibranchs this interval is bridged by the palps and the oral grooves; in the cyphonautes by the ciliated tract of the funnel. The cyphonautes being a larval form of probably archaic character its method of feeding is of particular interest.
Local variations in the colour pattern of the prawn Leander serratus (Pennant)
Authors: Carlisle D. B.
Published: May 2009

During investigations into the endocrinology of Leander ( =Palaemon) serratus (Pennant) several differences in physiology (which will be reported in this Journal at a later date) have been found between the prawns from Plymouth and those from Roscoff on the north coast of France. These experiments involved the repeated handling and the close examination of about a thousand prawns from Roscoff and many more from Plymouth. Increasing familiarity with these animals led to the realization that the two samples could readily be distinguished by eye. It was not always possible to determine the provenance of a single individual in this way, but any group of five or six could be told at a glance. A detailed examination of the external morphology showed that the characteristic differences by which the provenance of these animals could be determined lay not in any anatomical feature but in the disposition and arrangement of the chromatophores which form the pattern on the dorsal side of the cephalothoracic shield and the anterior part of the abdomen. Great individual variations were to be seen, but differing trends of development of the patterns were found in the two populations. There was some degree of overlap between the populations, but only about 15% of the prawns lay in this region of overlap and thus failed to bear the marks of their locality; the remaining 85% could be assigned to either Roscoff or Plymouth with little difficulty. Recently I have been able to examine about forty prawns from Concarneau, on the Atlantic coast of France, and these again are mostly different from either of the other two samples.
The dichotomous species of Codium in Britain
Authors: Silva Paul C.
Published: May 2009

The nameCodium tomentosum(or its nomenclatural synonymC. dichotomum) has been applied to dichotomous representatives of the genus in the British Isles ever since the genus was established by Stackhouse in 1797. The purpose of this paper is twofold: to show that three distinct species are involved; and to clarify the nomenclature.

I am grateful to the directors and curators of the following herbaria for the loan of specimens: British Museum (BM); Royal Botanic Garden, Edinburgh (E); Farlow Herbarium, Harvard University (FH); University of Glasgow (GL); Royal Botanic Gardens, Kew (K); Rijksherbarium, Leiden (L); Linnean Society of London (LINN); University of Michigan (MICH); New York Botanical Garden (NY); University of Oxford (OXF); Museum National d'Histoire Naturelle, Laboratoire de Cryptogamie, Paris (PC); Marine Bio-logical Association, Plymouth (PL); Naturhistoriska Riksmuseet, Stockholm (S); Trinity College, Dublin (TCD); University of California, Berkeley (UC); United States National Museum (US). Liquid-preserved and dried material, which has been placed in the Herbarium of the University of California, was kindly provided by Dr Sheila Lodge, Dr Betty Moss, Dr Mary Parke, Dr Mairfn de Valera, and Dr M. A. Wilson. Special thanks are due to Dr Mary Parke for her sustained interest, encouragement, and help in this study
Studies on pigment-activating substances in animals I. The separation by paper electrophoresis of chromactivating substances in arthropods
Authors: Knowles Francis G. W. , Carlisle David B. , Dupont-Raabe Marie
Published: May 2009

It has been established that many substances can bring about a change in position of pigments in crustacean chromatophores (Florey, 1951). The extracts of certain animal tissues (pituitary, crustacean sinus-gland and post-commissure organs, insect brain and corpora cardiaca) are especially active (Brown, 1940; Knowles, 1953; Dupont-Raabe, 1952; Thomsen, 1943); there is evidence that these tissues intervene in the normal colour change of the animals which possess them and that their products may properly be considered as hormones. On the other hand, many species which do not themselves possess chromatophores (oligochaetes, molluscs, and many insects) have nevertheless been shown to contain substances in their tissues which will, after injection into crustaceans, initiate pigment movements (Scharrer, 1954). It has not yet been ascertained whether these pigment-activating substances chemically resemble normal colour-change hormones or whether the pigment movements they produce are pharmacodynamic effects irrelevant in the study of colour physiology.
Porphyrin pigments in the tectibranch molluscAkera bullataO. F. Müller
Authors: Kennedy G. Y. , Vevers H. G.
Published: May 2009

The sudden appearance ofAkera bullatain the static water tanks of H.M. Dockyard, Devonport, provided specimens for the investigation of pigments. Morton & Holme (1955) have given an account of certain aspects of the biology of this interesting tectibranch mollusc.
Vitamin A and carotenoids in certain invertebrates: IV. Mollusca: Loricata, Lamellibranchiata, and Gastropoda
Authors: Fisher L. R. , Kon S. K. , Thompson S. Y.
Published: May 2009

Apart from a general account (Kon, 1954) of our work on vitamin A and carotenoids in invertebrates, our publications so far (Kon & Thompson, 1949a, b; Batham, Fisher, Henry, Kon & Thompson, 1951; Fisher, Kon & Thompson, 1951, 1952, 1953, 1954, 1955) have been concerned only with marine Crustacea. We have also studied, during our investigation of the metabolism of vitamin A and its possible precursors in the sea, numerous species from most other phyla of marine invertebrates. Except for the nematode worm,Anisakis physeterisBaylis, taken from the stomach of a sperm whale, the only two phyla of invertebrate animals in which we have so far found vitamin A are the Arthropoda and the Mollusca. The vitamin was present in at least some species from each of the molluscan classes, Loricata, Gastropoda, Lamellibranchiata and Cephalopoda, but we have no information yet about the Solenogastres or the Scaphopoda of which we have analysed no representatives. So far as our studies were concerned, the cephalopods differed considerably from the other molluscs examined, and the relatively large amount of information they have provided will be more conveniently presented in a subsequent paper. The account which follows, therefore, deals only with species from the first three classes just listed.