bluuebunny/crossref_metadata_2025 huggingface dataset:
The Mode of Life ofArenicola MarinaL.
Authors: Wells G. P.
Published: May 2009

Large, common, tough, the lugworm is an outstandingly good object for anatomical and physiological work. Its mode of life has not yet been clearly worked out, and one must know how an animal lives if one wishes to understand its structural and functional peculiarities. Burrowing as it does in muddy sand, the lugworm cannot be watched under natural conditions (except on the rare-occasions when itshows itself on the surface). Existing accounts of its behaviour inthe field are therefore practically confined to the form of the burrow which it excavates. The present paper attempts to synthesize, partly from field observations and partly from laboratory studies ofthe worm's activities, a coherent picture of its daily life.
Note on Selective Feeding by Calanus
Authors: Harvey H. W.
Published: May 2009

The rates at which Calanus finmarchicus eat both carmine particles and the diatom Nitzschia closterium have been investigated by Fuller & Clarke (1936) and Fuller (1937). They found that the number of Nitzschia or of carmine particles, eaten by a Calanus in unit time, was proportional to the concentration of Nitzschia or of particles in the water. Lucas (1936) also found that Neomysis and Eurytemora ate Nitzschia at rates which were roughly proportional to the concentration of diatoms in the water over fairly wide limits.

During 1935 I had made, as part of another investigation, three experiments on the rate at which Calanus eat diatoms of larger size. This happened much more rapidly than Fuller found to be the case with suspensions of Nitzschia. Meanwhile Lowndes (1935) had concluded, from direct observations, from the anatomy of their mouth-parts and from observations by Lebour and Marshall, that Calanus should be able to catch and select food. He concludedthat Calanus does not depend entirely upon its (automatic) filtering mechanism for all the food it obtained.

The quantitative data which I had collected in these three experiments, in conjunction with those published by Fuller & Clarke (1936,1937), were suitable for examining this contention. They suggested that the animal when fed with diatoms of moderate size selected by catching the species it preferred, while it automatically filtered the minute Nitzschia. With these possibilities in view, experiment N 90 was made in order to link up the three experiments with the numerous experiments made by Fuller (1937).
The Eggs and Larvae of the British Prosobranchs with Special Reference to those Living in the Plankton
Authors: Lebour Marie V.
Published: May 2009

Molluscs are very important members of our marine fauna, and, since many of them are planktonic in their early stages, they contribute largely to the number of organisms available as food for plankton-eating animals. The present work includes the prosobranchs only, particularlythose from Plymouth which have been specially studied during the last few years. Several papers have already been published dealing with the Plymouth species (Lebour, 1931–6), and these are referred to in due course. The present paper brings together the above work and that of others and summarizes our knowledge of the larval prosobranchs of Britain, with a description of the eggs. Naturally there are still many gaps, but it is hoped that these may be filled in time. A preliminary paper on the subject has already appeared (Lebour, 1933f). Closely related foreign species are referred to for comparison with our British forms. Original notes on certain species and information on the echinospira larva ofCapulus ungaricusare given here for the first time. Figures of typical eggs and larvae are given.
The Supply of Iron to Diatoms
Authors: Harvey H. W.
Published: May 2009

The nature of iron occurring in sea water, and its utilization by diatoms, is discussed.

Diatoms in the sea obtain many thousand times more iron than calculation shows they can obtain by diffusion of iron ions from the surrounding water.

Evidence is presented that ferric hydroxide is readily adsorbed on the surface of diatoms.

It is shown that colloidal and larger particles of ferric hydroxide or phosphate can be utilized by, and support the growth of diatoms.

Experiments show that the diatoms Nitzschia closterium and Lauderia borealis require, for continued growth, a very small quantity of iron compared with that found on, and in, diatoms taken from the open sea.

It is contended that iron hydroxide adsorbed on diatoms is in contact with an interface where its solution, and subsequent passage into the cell, is probable.
Oxygen Production by the Diatom Coscinodiscus Excentricus Ehr. in Relation to Submarine Illumination in the English Channel
Authors: Jenkin Penelope M.
Published: May 2009

1. A method, due to Poole & Atkins, is described for computing the total available energy at any depth in the sea, in joules or g.-cal.

2. The oxygen production of pure cultures of the diatom Coscinodiscus excentricus Ehr. was measured by the Winkler method after exposure of the diatoms in bottles at known depths in the sea. 3. The results of simultaneous measurements of oxygen production and of energy are given for 6 days in July and August 1933 and 1934.

4. Factors, other than light, that might affect the rate of oxygen production in the experiments are discussed and shown to be negligible. It is assumed that diatoms can use energy for photosynthesis equally well in all parts of the visible spectrum.

5. When the energy flux during the exposures is less than 75 joules or i-8 g.-cal. per cm.2 per hr., the oxygen production is directly proportional to the energy. The utilization of the available energy then amounts to about 7%.
Relation of Bacteria to Diatoms In Sea Water
Authors: Waksman Selman A. , Butler Margaret R.
Published: May 2009

1. Dead marine diatom plankton was found to undergo rapid oxidation and decomposition when added to fresh sea water. This was measured by oxygen consumption, nitrogen liberation, phosphate regeneration and bacterial multiplication.

2. Living diatoms added to sea water and placed in the dark continued to absorb oxygen; they were rather resistant to bacterial attack.

3. Diatom-rich marine plankton also absorbed oxygen, while the phosphorus was gradually regenerated. The bacteria did not increase in numbers in correspondence with the oxidation of the fresh diatom material.

4. When sea water in which photosynthesis was allowed to proceed for varying periods of time was placed in the dark, rapid oxidation of the freshly synthesized material took place, as indicated by oxygen consumption and phosphate liberation. Although there was a greater number of bacteria in the water in which photosynthesis took place, the oxidation of the fresh diatom material was not accompanied by any large increase in bacteria; in fact a decrease in numbers was frequently observed.
The Triradiate and other Forms ofNitzschia Closterium(Ehrenberg) Wm. Smith, FormaMinutissimaof Allen and Nelson
Authors: Wilson Douglas P.
Published: May 2009

1. The natural history in culture of the species ofNitzschiaoriginally isolated from the sea by Allen & Nelson (1910) and grown at Plymouth and elsewhere ever since has been studied. It is shown that three main types of cell exist: normal with two arms (rostra), triradiate with three arms and ovals with none. Both normals and triradiates produce ovals by division, and the ovals so produced can multiply to form further ovals, or can grow either two or three arms, generally two, to form normal or triradiate cells.

2. Ovals are more readily produced under good lighting conditions than under weak illumination.

3. The cell wall is very lightly silicified, and the cells, unlike those of most diatoms, can elongate without auxospore formation. The maximum, and with it apparently the average, cell size of successive subcultures is variable.

4. When triradiates are present they may, and frequently do under good cultural conditions, multiply faster than normal cells and finally may almost completely dominate the cultures. Now and again a proportion of the triradiate cells shorten one arm and gradually pass, during successive divisions, into the normal condition. There is a greater tendency for this process to take place in the autumn than at any other time. There was a notable instance in November 1941 when several cultures at Plymouth and at Hull simultaneously produced normals by this method on an extensive scale.

5. There is evidence that under unfavourable cultural conditions triradiates tend to be eliminated.

6. A cruciform type of cell has appeared occasionally in several cultures, but it has not been possible to obtain pure cultures of it, for the type appears to be somewhat unstable and readily reverts to the other forms. It has, however, persisted for a long time and for very many generations.

7. It is shown that the triradiate type occurs in nature, and there is no reason to suppose that it is an abnormal form due to culturing.

8. The nomenclature is discussed and it has been decided for the time being to retain the name Allen and Nelson originally gave to it, although there is a possibility that it is a species separate fromNitzschia closterium(Ehr.) W. Smith.
The Utilization of Organic Phosphorus by Phytoplankton
Authors: Chu S. P.
Published: May 2009

Cultural experiments were made with marine organisms in enriched crude sea water and in bacteria-free cultures with the phosphorus supplied in different forms. It was found that pyrophosphate cannot be utilized as a source of phosphorus as effectively as orthophosphate by the organisms cultured, i.e. Phaeocystis Pouchetii, Skeletonema costatum and Nitzschia closterium. Growth of Phaeocystis Pouchetii was a little better and lasted longer when phytin was supplied to natural sea water as a source of phosphorus than when orthophosphate was supplied. Phytin can also support a growth of Skeletonema costatum and Nitzschia closterium as good as, or a little better than, orthophosphate.

The organic phosphorus compounds used in these experiments were found to be broken down into orthophosphate in natural sea water. In bacteria-free cultures phytin and glycerophosphoric acid can be effectively used as such by Nitzschia closterium forma minutissima as a source of phosphorus, while sodium nucleinate and lecithin can not be effectively used as such. The organic phosphorus dissolved out from the blades of Laminaria can also be utilized by this diatom as effectively as orthophosphorus.

It would seem, therefore, that not only the dissolved orthophosphate as generally assumed, but the dissolved organic phosphorus in the sea may also be absorbed and utilized by plants.
The Genital Ducts of Theodoxus, Lamellaria and Trivia, and a Discussion on their Evolution in the Prosobranchs
Authors: Fretter Vera
Published: May 2009

The prosobranchiate gastropods are divided into three orders, the Archaeogastropoda, the Mesogastropoda and the Stenoglossa. In the first of these groups the gonad is connected with the right kidney by a duct which is developed from the ovary, and the sex cells escape to the posterior end of the mantle cavity through the right ureter. The eggs are usually shed singly into the sea where fertilization occurs. In the Mesogastropoda and Stenoglossa the right kidney is not developed and the ovarian duct leads to a short and narrow section of the genital duct which is typically ciliated, and may communicate with the pericardium by a gonopericardial duct and passes anteriorly to a long glandular tract running forwards to the mouth of the mantle cavity. This glandular section is incipient in the archaeogastropod Calliostoma zizyphinum. It is probably formed, as Thiele (1935) suggests, by an ectodermal intucking and will be referred to as the pallial oviduct, for it lies anterior to the opening of the original right kidney, and must be derived from the ectoderm of the mantle (Bourne, 1908; Giese, 1915). The short duct which links it with the ovarian duct will be termed the renal oviduct: in Paludina (=Viviparus), in which its development has been investigated (Drummond, 1903), it is formed from the vestige of the right kidney, and even in the highly specialized Stenoglossa it retains the connexion with the pericardium which is characteristic of the right and left kidneys of the archaeogastropods. Similarly, in the male system of the Mesogastropoda and Stenoglossa there can be distinguished a testis duct, which is connected to the posterior end of the mantle cavity by a renal vas deferens, and this in turn is followed by a pallial vas deferens.
Vertebral Variation in Teleostean Fishes. III. Isospondyli
Authors: Ford E.
Published: May 2009

This paper does not give a detailed description of the backbone of any one of the eight isospondylid species examined. Instead, selected data have been used in a discussion of the broad principles of vertebral variation, as seen in fishes of the order Isospondyli. This was considered to be of greater value than a catalogue of vertebral details for each of a small number of already wellknown species. Even so, sufficient has been said to enable any worker to identify the backbone of any one of the eight species, as well as to obtain a most discriminative description of the backbone of any other species of Isospondyli he may examine. A distinction is drawn between the countable vertebral characters, which are statistics for the precise measurement of vertebral variation, and the 'marker' characters, which provide the means for recognition 'on sight'. It is believed that vertebral characters of both kinds might be profitably employed in the study of different biological populations of the same species. The correlation between vertebral characters and other bodily features, such as keeled scales, position of fins and anus, and contour of body cavity, receives attention, and is related to metamerism. Finally, the occurrence of autogenus vertebral arches and the bifid condition of the neural spines in the isospondylid backbone is shown to be primitive and not restricted to the order.
A Note on the Capture of Prey bySepia OfficinalisL.
Authors: Wilson Douglas P.
Published: May 2009

There are various short and incomplete accounts of the capture of prey bySepiascattered throughout the literature (Grimpe, 1928; Hertling, 1929; Holmes, 1940, are all typical and fairly recent), but I have not found any really satisfactory figures. Those I have seen are little better than rough sketches (Grimpe, 1928, p. 372; Naef, 1923, text-fig. 304b; Tompsett, 1939, plate i, fig. 2) and there do not appear to be any photographs at all. A few observations, and some photographs I have taken recently should therefore be of interest, especially as the photographs reveal some points that do not appear to have attracted attention previously. The final stages of the capture take place so rapidly that the eye fails to observe the details, whereas photographs can be studied at leisure afterwards.

The specimen ofSepiathat forms the subject of these pictures was of medium size with a shell about 12 cm. long. It had been living in a tank, with others of about the same size, for several months, during which time it had been fed on living prawns. It was photographed in mid-November when the water temperature was 12.5° C. (in a later paper I shall show that below about II° C.Sepiaoften ceases to feed). The photographs were taken by flashlight on two evenings between 7 and 8.30 p.m., the tank being lit, for viewing purposes, by a 100 W. bulb in a reflector above one end (the left side in the pictures). Each photograph was taken at sec. with one Baby Sashalite bulb and a synchronizer of my own design, the shutter being released electrically.
On the Development of Muggiaea Atlantica Cunningham
Authors: Russell F. S.
Published: May 2009

In September 1937 Muggiaea atlantica Cunningham was very abundant off Plymouth. The presence of large numbers of eudoxids in the plankton afforded an opportunity to rear the early stages of this siphonophore. The development of M. kochi (Will) was worked out by Chun (1882, 1913), and he also described the eudoxid of that species. The eudoxid of M. atlantica has, however, never been described for certain. The allocation of eudoxids collected in the plankton to their respective species is necessarily fraught with uncertainty when more than one species is present. Throughout the whole of September 1937 M. atlantica was the only species of siphonophore to be found off Plymouth, and there can be no reasonable doubt that the eudoxids described below belonged to that species and that the development of the early stages from their eggs is that of M. atlantica.

For the terminology used in the description of the eudoxid I have followed Totton (1932), to whom I am grateful for helpful advice.

The Eudoxid

The bract (Fig. 2 a) is cone-shaped with a broad flat suture running from its apex to the base. The edges of the suture are raised into a slight flange. The right edge is continued downwards into a sweeping curve while the left edge cuts away horizontally at its lower end; the bract is thus asymmetrical. There is a slight cavity on the lower surface in which the somatocyst is centrally placed. The general form of the bract can also be seen in the different views of the whole eudoxid given in Fig. 1.
The Ecology of the Tamar Estuary I. Introduction
Authors: Hartley P. H. T. , Spooner G. M.
Published: May 2009

During 1936 and 1937 extensive physical and faunistic studies of the Tamar Estuary were made by several workers at the Plymouth laboratory. These investigations, though conducted independently and with different immediate aims, proved to have considerable bearing on one another, and each worker benefited by occasions for co-operation. As the work proceeded it became clear that one of the most important aspects of each investigation was the bearing it had on the balance of life in the estuary as a whole. It was decided to publish the results of these studies in a series of papers in which each contributor should lay due emphasis on data having possible bearings on the problems studied by the others, so as to present as complete a picture as possible.

Studies have been made of salinity, temperature, penetration of daylight, macro- and micro-fauna of the intertidal zone, the sessile flora and fauna of the buoys, the fishes and their food, and the birds which frequent the flats and channels. Other studies are contemplated. In the work on light penetration and on quantitative estimates of the fauna of the mud-flats, no comparable data have hitherto been procured in this country.

The Tamar is the largest of the rivers which flow into the west end of Plymouth Sound. It is tidal for nearly 19 miles (30 km.) of its course. Rather over 3 miles (5.5 km.) from the sea it is joined by the River Lynher to form the Hamoaze, an estuary common to the two rivers.
A biological difference between natural sea waters
Authors: Wilson Douglas P.
Published: May 2009

The work of F. S. Russell on plankton animals as indicators of different water masses, particularly the species Sagitta setosa J. Müller and S. elegans Verrill, and of Atkins, Harvey and Cooper on plant nutrients, have pointed the conclusion that the water in the English Channel, in the neighbourhood of Plymouth, was consistently richer in nutrients and plankton in the 5 or 6 years prior to about 1930 than it has been at any time since. (See Russell, 1935, 1936a, 1939; Cooper, 1938; Armstrong & Harvey, 1950; Harvey, 1950.) The comparative infertility of the sea in this area in the 1930's, and until the present time, has been shown not only by the low winter phosphate- maximum, and by the sparse plankton characterized by the presence of S. setosa, but also by the reduced numbers of young fishes surviving their early larval stages after the summer spawning (Russell, 1939).
Chemical properties of the sea water in the neighbourhood of the Labadie Bank
Authors: Cooper L. H. N.
Published: May 2009

A number of excursions to the Celtic Sea have been made, first, to obtain for Dr D. P. Wilson water as contrasted as possible with that in the English Channel near Plymouth, and secondly to obtain answers to hydrographical queries. This paper presents some of the chemical findings which may prove to be relevant to Wilson's investigations on the development of the young planktonic stages of invertebrates. Since not all sea water in the Celtic Sea was likely to be equally suitable for his work, some means was needed for quickly assessing waters on the spot. There are a number of objections to the use of phosphate or other chemical analyses on board so that examination of plankton hauls was chosen. Suitable water was selected on the basis of the bulk and variety of zooplankton and the presence of species known to indicate ‘elegans’ water. The 2 m. stramin ring-trawl, fished for the standard half-hour oblique haul, was used.
The development and early stages of the ascidian Pyura squamulosa (Alder)
Authors: Millar R. H.
Published: May 2009

In the family Pyuridae the larval and post-larval stages are known only in Halocynthia pyriformis (Rathke) and Boltenia echinata (L.). Berrill (1948) has pointed out that this is the least specialized family of the Pleurogona and that its larvae are therefore of particular interest.

On 1 August 1950 specimens of Pyura squamulosa (Alder), up to 36 by 30 mm., were collected from boulders at low-water level in the Sound of Kerrera, Argyll. They were taken on the following day to the Marine Station, Millport, and there kept in running sea water until 4 August, when artificial fertilizations were carried out.
Notes on the reproduction and early development of the cirratulid Tharyx marioni (St Joseph)
Authors: Dales R. Phillips
Published: May 2009

The larval development of the Cirratulidae is not well known, although an account of the development of Raphidrilus nemasoma Mont, was published by Sokolow in 1911 (under the name of Ctenodrilus branchiata), and of Audouinia tentaculata (Montagu) by Wilson in 1936. Apart from these two publications, only scattered observations may be found in the literature, and these are listed by Wilson (1936). Unfortunately, attempts to rear the larvae of Tharyx marioni (St Joseph) beyond the hatching stage have failed, and as it seems unlikely that further data may be gathered for some time, such results as have been obtained are presented here.

The main points of interest in the development and reproductive habits of T. marioni are: (i) the adults are atoquous; (ii) the eggs are comparatively large and yolky, and unlike Audouinia tentaculata, the pelagic stage is omitted; and (iii the larva on hatching is achaetous, as in other cirratulid larvae.
The determination of silicate in sea water
Authors: Armstrong F. A. J.
Published: May 2009

Silicon in sea water may be present in suspension, in particles of clay or sand, as a constituent of diatoms, etc., or in solution. Some silicon in solution occurs in the form of silicate. This is usually estimated by the colorimetric method of Diénert & Wandenbulcke (1923), which makes use of the yellow colour of the silicomolybdic acid which is formed when ammonium molybdate and sulphuric acid are added to the water (Atkins, 1923). The colour may be compared with that of standard solutions of picric acid (Diénert & Wandenbulcke, 1923) or potassium chromate (Swank & Mellon, 1934). The method is simple but the colour in sea water is often faint and is not easy to match visually, nor is its intensity strictly proportional to the concentration of silicate. Less colour is produced in sea water than in standard solutions made with distilled water and this ‘salt error’ must be allowed for (Brujewicz & Blinov, 1933; Wattenberg, 1937; Robinson & Spoor, 1936).
Autecology and the species problem in Fucus
Authors: Burrows Elsie M. , Lodge Sheila
Published: May 2009

On the rocky shores of the British Isles three species of Fucus are commonly found as components of the intertidal algal belt, namely, F. spiralis L., F. vesiculosus L. and F. serratus L. A fourth species, F. ceranoides L., occurs in places subject to the influence of fresh water but, although it may be important in connexion with the interacting processes to be described below, F. ceranoides is omitted from the present discussion because as yet too little is known of its autecology. Under the conditions prevailing in the characteristically zoned algal flora of an undisturbed region of a rocky coast, descriptions of the three species can be applied which fairly effectively distinguish one from the others. The chief characters used for this purpose are shown in Table I.
Littoral diatoms from the Salstone, near Plymouth
Authors: Hustedt F. , Aleem A. A.
Published: May 2009

The diatom flora inhabiting the muddy shores and bottoms off Plymouth has received little attention in comparison with the fauna associated with such muds. Since a large number of the microfauna depend, to a great extent, upon the diatoms as a source of food (Mare, 1942), a knowledge of the latter is there-fore desirable.
Gregariousness and Some other aspects of the setting behaviour of Sipirorbis
Authors: Knight-Jones E. W.
Published: May 2009

Further study of the phenomenon of gregariousness during settlement, demonstrated in the oyster Ostrea edulis (Cole & Knight-Jones, 1949; Knight-Jones, 1951) and the barnacle Elminius modestus (Knight-Jones & Stephenson, 1950), seemed to require laboratory experiments, for which a viviparous animal with a brief, lecithotrophic, pelagic stage appeared to be needed.
Age and growth ofCallionymus lyraL.
Authors: Chang Hsiao-Wei
Published: May 2009

The Common Dragonet,Callionymus lyraL., is one of the commonest fishes in the Plymouth area, and is widely distributed in European seas. Recent reports indicate that it occurs also off the coast of West Africa (Fowler, 1936; Poll, 1949). This fish, like others of the genus, attracts attention because, although it has very little economic importance, it is strikingly coloured and the sexes are markedly different. Work has been done on the breeding by Holt (1897, 1898), and by Holt & Scott (1898); on ova and larvae by M'Intosh (1885), M'Intosh & Prince (1889), Cunningham (1891), Holt (1897), Ehrenbaum (1905–9), Fage (1918), Mielck (1925), Duncker, Ehrenbaum, Kyle, Mohr & Schnakenbeck (1929); on seasonal abundance and distribution of post-larvae off Plymouth by Russell (1930–47) and Corbin (1948); and on the skeleton by Günther (1861) and Ford (1937). The mature males are provided with remarkable secondary sexual characters both in coloration and in relative lengths of snout and of median fins, which render them so different from the females that they were originally regarded as different species and known as the Gemmeous Dragonet (maleC. lyraL.) and the Sordid Dragonet (femaleC. lyraL.=C.dracunculusL.) respectively (Donovan, 1808; Yarrell, 1859; Couch, 1863). The sexual dimorphism and seasonal variation of this species has been much studied by Holt (1898), Smitt (1892–95), Gallien (1934), Letaconnoux (1949) and Desbrosses (1949). Very little information has so far been provided about its age and growth, with which the present paper deals.
Contributions to the biology of the mackerel, Scomber scombrus L. III. Age and growth
Authors: Steven G. A.
Published: May 2009

The first serious attempt to determine the age and growth rate of the common mackerel (Scomber scombrus L.) appears to have been made by Captain Atwood in 1856 (quoted by Brown Goode, 1884, p. 116) in the Massachusetts Bay area of northern North America. Small fish caught by Atwood in October of that year measuring 6½–7 in. in length (16.5–17.5 cm.) he believed to be the young of the year (i.e. they belonged to the O-group). Mackerel belonging to this group he calls ‘spikes’. ‘Blinks', ‘tinkers’ and ‘second size’ fish he assigns to the I-, II- and III-year age groups respectively, but unfortunately gives no data as to the sizes of those categories, merely stating that everyone well acquainted with mackerel makes the same groupings ‘as there seems to be a line of demarkation between the different kinds which stands out prominently’. Sixteen years later, on 27 July 1872, Malm (1877, p. 409) observed large numbers of small mackerel close inshore in the Gullmarfjord near Christineberg. Several tons of those mackerel were enclosed in a seine, but only ten specimens were retained as all the others escaped through the meshes. These ten fish ranged in length from 67 to 100 mm. and Malm surmised their age to be 13 months. Collett (1880, p. 18) stated that on the coast of Norway I-year-old mackerel are ‘fingerlang’. To fish of 20 cm., taken at the end of August, he ascribed (without supporting data) an age of 2 years, with sexual maturity supervening at 3 years at an unspecified length.
Studies on the growth of marine phytoplankton III.Prorocentrum micansEhrenberg
Authors: Kain Joanna M. , Fogg G. E.
Published: May 2009

The last of the organisms to be studied in this series was chosen as a representative of the Dinophyceae. The treatment ofProrocentrum micansEhrenberg has been similar to that ofAsterionellajaponicaCleve & Müler ex Gran (Kain & Fogg, 1958 a) andIsochrysis galbanaParke (Kain & Fogg, 1958b). The present paper includes a discussion of the results for all three organisms in the light of work by previous authors.
A new species and genus of Brachiopoda from the western approaches, and the growth stages of the lophophore
Authors: Atkins D.
Published: May 2009

A new species and genus of brachiopod has been dredged by R.V.‘Sarsia’ on three cruises to the Western Approaches of the English Channel and two to the La Chapelle Bank region. In general appearance it closely resembles Dallina septigera (Lovén) with which it appears to have been confused by Fischer & Oehlert (1891).

In 1956 it was obtained on 13 June at position 48° 33′ N., 10° 05′ W. at a depth of 570–770 fathoms, four specimens of shell length 17–25 mm were taken together with seven D. septigera.
Histology of the light organs of Pholas dactylus (Lamellibranchia)
Authors: Nicol J. A. C.
Published: May 2009

The piddock, Pholas dactylus L., gives off a luminous secretion when irritated. The luminous glands which produce the secretion are two longitudinal stripes in the exhalant siphon, a pair of triangular organs in the mantle cavity near the base of the siphon, and a stripe around the ventral rim of the mantle (Panceri, 1872).

The histology of the light-organs has been described several times. A light-organ is covered by a simple columnar ciliated epithelium, below which are many glandular cells, which discharge through the surface epithelium. The outer part of the glandular layer consists of a mass of large mucus cells. Deeper lies a second glandular region containing large cells with long necks that extend to the external epithelial surface. Dubois (1892, 1914, 1928) believed that the photogenic tissue was made up of two kinds of secretory cells; these were the superficial ciliated cells, which possessed glandular bases (fixed secretory cells); and deeper lying glandular cells derived from clasmatocytes (migratory secretory cells). Rawitz (1891) clearly distinguished a mucous from an underlying photogenic layer. The latter, according to Förster (1914), contains pyriform cells with long necks. He believed that he could distinguish a secretory cycle in the photogenic cells. Exhausted cells at the beginning of the cycle possessed an alveolar cytoplasm; granules began to appear in the cytoplasm; the granules increased in number and stained intensely with iron haematoxylin. Those photogenic cells which were filled with granules were in the active secretory state. Transitional stages between the inactive (or depleted) cells and the active (granular) cells were rare.
The water flow into the English Channel from the south-west
Authors: Cooper L. H. N.
Published: May 2009

The physical oceanography of the shallow seas south-west of the British Isles ismuch influenced by the exchanges of waters around headlands between neighbouring areas of the sea. These are
Massive upward displacement in the deep ocean
Authors: Cooper L. H. N.
Published: May 2009

For a third of a century many and varied studies on sea water have been concentrated upon a single accessible shallow-water station in the English Channel, EI, supplemented by more extensive excursions usually designed to test working hypotheses. This concentration of effort has been richly rewarded. In deep-water oceanography a similar approach is appropriate; a standard station, ‘Cavall’ has therefore been selected in the north-eastern Bay of Biscay in 4700 m of water at lat. 46° 30' N., long. 8° 00' W., nominal, a position worked by the Danish Research Vessel ‘Dana’ in 1922 and 1930. It is not only the nearest deep water position to Plymouth but it has best possible coverage by the Decca Navigator system. For our experimental programme it is essential that the station positions be maintained and repeated precisely. To achieve this a working Decca chartlet (Fig. 1) on a scale of 1:20,000 has been prepared for each station from a portion of the Admiralty Decca Lattice chart no. L 1104. On this a circle of radius one mile is inscribed. Throughout operations the ship is maintained within this circle by stopping work when necessary and steaming back on Decca co-ordinates towards the centre, or beyond to pre-compensate expected drift.
The fecundity of English Channel plaice
Authors: Bagenal T. B.
Published: May 2009

This paper is the fourth in a series dealing with the fecundity of flatfish (Bagenal 1957 a,b, 1958), and is concerned with the egg numbers in ripening female plaicePleuronectes platessa L. caught in the English Channel.

On 27 November 1957, eighty-five plaice with maturing ovaries were caught in Rye Bay, Sussex; on I December, eight similar fish were caught in Lyme Bay, and duringDecember sixty-four locally caught female plaice were brought in to the Plymouth Laboratory. The dates of the collections were chosen because in January 1957 I had found that a small proportion of the Plymouth plaice were spent. All the fish caught in November and December were at a suitable stage for fecundity estimation: that is, the eggs were well developed though none had begun to turn translucent.
The occurrence of Ingolfiella in the Eddystone shell gravel, with description of a new species
Authors: Spooner G. M.
Published: May 2009

Among the various small Malacostraca that have lately been found living interstitially in the Eddystone shell gravel (see Spooner, 1959 a,b), one of the moreremarkable is a new member of the genusIngolfiella. This genus of small colourless blind amphipods occupies a very isolated position, and is customarily given the rank of a separate suborder. The six species hitherto recognized are listed in Table i, and their geographic relationships shown in Fig. 5 (p. 328).
William H. Searle, B.E.M.
Authors: Wilson D. P.
Published: May 2009

By the death at the age of 84 of Mr William H. Searle there passed away, on 6 April i960, one who had served the Laboratory longer than anyone else and who, during his 63 years as fisherman-collector, had installed himself in the affections of countless biologists the world over. From December 1895 until his retirement on 30 September 1958 his assiduous and unwearied devotion to his collecting duties, year in and year out whatever the weather, on the shore or in his boats, earned him the lasting gratitude of all those innumerable research workers, teachers and students who relied on ‘Bill’ to procure living material for their researches or studies. He, more than anyone else, knew where the animals were to be found, how to capture them without damage and how to ensure their safe arrival at the Laboratory hours later. More than one student who had been collecting on the shore alongside Bill has later been astonished to observe the large and varied assortment of creatures emerging alive and kicking from one small and tightly packed basket. He had a keen eye for the little things—Gromia, praniza larvae and the like, from the rock crevices he split open with his crow-bar. These he would carefully transfer from silted rock surface to honey jar on the point of his pocket-knife. He knew well their scientific names, though foreigners would often have difficulty in recognizing them when pronounced with a strong Devonshire accent. It was usually the old names current during his youth that he knew, and he was not alone in deploring the activities of systematists in so frequently changing and re-changing so many of them.
Plant hormones in marine phytoplankton, zooplankton and sea water
Authors: Bentley Joyce A.
Published: May 2009

Studies by many workers on the subtle ecological relationships of marine organisms suggest that the distribution of these organisms may be controlled, at least in part, by trace organic substances in their environment. These substances may range from ‘toxins to vitamins and hormones’ (Lucas, 1955). Saunders (1957) has reviewed the interrelations ofdissolved organic matter and phytoplankton and considered the possible roles of organic metabolites in the growth of the algae. The presence of several vitamins, for example, B12, thiamin, niacin and biotin, has been demonstrated in natural waters, but the possible occurrence of plant hormones has not previously been considered.
Chemical changes in sea water off Plymouth during 1959
Authors: Armstrong F. A. J. , Butler E. I.
Published: May 2009

Analyses of sea water collected during 1959 at the International Hydrographic Station E1 (lat. 50° 02′ N., long. 4° 22′ W.) are given here in the same form as earlier reports (Armstrong, 1954, 1955, 1957, 1958; Armstrong & Butler, 1959, 1960). The methods of collection and analysis remain the same. Salinities were determined by the Government Chemist, Department of Scientific and Industrial Research. We wish once more to thank Lt.-Cdr. C. A. Hoodless, D.S.C. and the crew of R.V. ‘Sarsia’, and Capt. W. J. Creese and the crew of R.V. ‘Sula’ for help at sea.
A contribution to the biology ofAstrorhiza limicola(Foraminifera)
Authors: Buchanan J. B. , Hedley R. H.
Published: May 2009

In the last few years the exceptionally large monothalamous arenaceous rhizopod,Astrorhiza limicolaSandahl, 1858, has been collected in appreciable numbers from the Blythand Plymouth areas of British coastal waters. These collections of the living animals have enabled the authors, both independently and jointly, to make certain observations of the behaviour of the animal, and of the structure of the test, which have not been appreciated hitherto. With the exception of two early accountsofA.limicola,one by Bessels (1875) under the nameHaeckelina giganteaand the other by Schultz (1915), very little appears to be known of the biology ofany member of the family Astrorhizidae.
The influence of temperature on the breeding and the moulting activities of some warm-water species of operculate barnacles
Authors: Patel Bhupendra , Crisp D. J.
Published: May 2009

Thorson (1946) considered in detail the earlier views of Appellöf (1912), Orton (1920) and Runnström (1928) that breeding activities of the majority of marine organisms were controlled by the temperature of the sea and referred to this as Orton's rule. RecentlyCrisp (1954) and Qasim (1956) also reviewed the existing literature on this subject in relation to barnacles and fish. By considering the seasonal availability of planktonic food in con-junction with Orton's rule, they explained why tropical species inhabiting cool temperate waters have a breeding season confined to the warmer months, whereas boreo-arctic species throughout their whole range breed only during colder months.
Red blood values in the plaice(Pleuronectes platessaL.)
Authors: Preston A.
Published: May 2009

The work reported in this paper forms part of a programme of investigation into the normal parameters of radiosensitive tissues in the plaice. The work was conducted prior to investigations into the effectsof ionizing radiations on these tissues, in order to form a backgroundto examinations of fish from areas of radioactive pollution resulting from the controlled disposal of radioactive effluent. Tissues were selected on the basis of known radiosensitive tissues in mammals and the work on red blood values reported here arose from these preliminary investigations.
Notes on the Inshore Plankton of Plymouth
Authors: Lebour Marie V.
Published: May 2009

During the years 1940–5 plankton samples were examined regularly from inside the Plymouth Breakwater, with the exception of a few months. Although it was not possible to do any quantitative work, special attention was given to larval forms, especially of the decapods, molluscs and annelids. The presence of these larvae gave a good idea of the breeding seasons of the various species. As it is only recently that many of these larvae have been identified, this is the first time that detailed specific notes have been made of their presence; and it is thought to be worth while to publish these results. To help those who wish to identify the larvae, a reference to a description of each species is given whenever possible, in square brackets after its name. It should be clearly understood that the absence of any species from these notes does not necessarily imply that it might not have been there, although all the samples were carefully examined. Most of the Coelenterates, the Cirripedia, Copepoda, and young fishes, are omitted here. Of the remaining ingredients of the plankton, various records were kept; and the occurrence of the more noteworthy of these forms, according to months, is shown in Table I.
An Interesting Young Velella in the Plymouth Plankton
Authors: Lebour Marie V.
Published: May 2009

On 2 February 1943, after some very fierce south-westerly storms, a curious object was found in the inshore plankton which proved to be the ‘float’ of a very young Velella in the Rataria stage. In order to be certain of its identity some small complete Velellas were compared. These were kindly sent by Miss Delap of Valencia, to whom I am much indebted. They ranged from 1.5 to 2 mm. across and were very similar to the young forms described and figured by Huxley (1858), who identified them with the Rataria of Eschscholz (1829). In this stage the float is growing and may already have the crest, a soft, much higher structure, projecting above it. In order to see the float clearly one of the Irish specimens, 2 mm. across, was macerated in 10% caustic potash, the float separating out and proving to be exactly similar to the Plymouth specimen.

The peculiar structure of this float and the fact that the available figures of the Rataria of similar size show only the external features make a short note desirable, for in the existing figures one cannot be certain of the exact extent and position of the float. So difficult was it to decipher that, although it seemed very probable that we had the float of a Velella, it was not possible at first to be certain.
On the Fertility of Marine Cladocera with a Note on the Formation of the Resting Egg in Evadne Nordmanni Loven and Podon Intermedius Lilljeborg
Authors: Cheng C.
Published: May 2009

A statistical study was made of the fertility of Evadne nordmanni, Podon intermedius, P. leuckarti and P. polyphemoides in the Clyde Sea-Area and of the former two species off Plymouth. The mean fertility of parthenogenetic females varies with different species. This is not correlated with the size of the species.

Within the species, Evadne nordmanni and Podon intermedius, there exists, in general, a positive correlation between the size and the fertility of parthenogenetic females.

The fertility of Evadne nordmanni is subject to seasonal variation. This is not correlated with fluctuations in the abundance of diatoms.

An inverse relationship was observed in Evadne nordmanni between the reproductive capacity of parthenogenetic females and the intensity of sexual reproduction.

A brief account was given of the formation of the resting egg in Evadne nordmanni and Podon intermedius.
The Life History of Patina Pellucida (L.)
Authors: Graham Alastair , Fretter Vera
Published: May 2009

Patina pellucida occurs in two facies with characteristics of habitat and structure, the latter' affecting mainly the shell. One variety, pellucida, which lives on the fronds of Laminaria, has a smooth, elpngated oval and low shell, which is transparent and brown in colour, with 2-8 blue rays radiating backwards from the summit which is placed at the anterior end; it is normally devoid of either epiphytic or epizoic growth. The soft parts are pigmented because of the translucency of the shell, the radular teeth only slightly worn, and the arrangement of the gut coils adapted to a long, narrow haemocoelic space. The second variety, laevis, lives in caves in the holdfasts of Laminaria, and has a rough, round and usually high shell, though the proportions are more variable than in the variety pellucida. The shell is opaque and brown in colour, with 2-46 blue rays and also red-brown ones more or less regularly alternating with them; it has a central summit and is frequently covered with growths of various sorts. The soft parts are not pigmented, the radular teeth are considerably worn, and the coiling of the gut modified to fit into the rounder haemocoel.

The life history may be summarized: the animals breed maximally in winter and spring, the planktonic larvae settling mainly in May as spat about 2 mm. in length. They grow so as to reach a length of about 5 mm. in the following autumn and 10 mm. after a year of sedentary life, becoming sexually mature at 5 mm. length. The majority of the animals die after a settled life of 12 months, but a few linger on into a second year: nearly all these belong to the variety laevis, living a sheltered life within the holdfast of the weed, not exposed like pellucida to the effects of wave action and storm.
The Hydroid of the Medusa Dipurena Halterata (Forbes)
Authors: Rees W. J.
Published: May 2009

Although the medusa Dipurena halterata (Forbes, 1846) is well known, and has been figured by a number of authors (e.g. Forbes, 1848; Browne, 1897), the hydroid of this peculiar species has remained unknown. This medusa is rather scarce at Plymouth (Russell, 1938). On May 3 1938 I had the good fortune to find at Plymouth a small hydroid of the Syncoryne type which later liberated young medusae, and these proved to be young specimens of Dipurena halterata.
On the seasonal Abundance of Young Fish. VI. The Year 1938
Authors: Russell F. S.
Published: May 2009

The present report continues the series of observations on the seasonal abundance of the pelagic young of teleostean fish in the plankton off Plymouth (Russell, 1938b), and gives the results for the year 1938. These results are published in the same form as in previous reports. The dates on which collections were made with the 2 m. stramin ringtrawl are given in Table I, and the monthly average catches of the young fish per half-hour oblique haul in Table II.
The Pelagic Phase in the Life History of the Amphipod Genus Bathyporeia
Authors: Watkin E. Emrys
Published: May 2009

The zonation of four species of the genus Bathyporeia, from high-water mark to low-water mark, in Kames Bay, Millport is given. B. pilosa occurs above the high-water mark of neap tides, B. pelagica is a mid-tidal form and B. elegans a low-water form. The latter, together with B. guilliamsoniana, extend beyond low-water mark. Of the population, as it occurs in the sand, 15 % are adult males, 26 % adult females, giving a proportion of adult to
immature forms of 4 1 : 59.

The analysis of forty-five tow-net samples taken across the bay at night shows that the same zonation of the species is maintained; the proportion of adults to immature forms in these samples, however, is as 57: 43, and of the 57 % of adults, 42 % are adult males, 15 % adult females.

When the samples are related to the day of the lunar month it is shown that the numbers increase in the tidal waters in the periods immediately preceding the full moon and preceding and partly overlapping the new moon. A nocturnal vertical movement appears to be a marked feature of a few benthic amphipdd families, but the factors which cause this migration are problematical and require much further investigation.