No general description of the Plymouth Laboratory of the Marine Biological Association of the United Kingdom has been published since that of Allen & Harvey (1928). Some information was, however, given by Russell (1947, 1948) in a survey of the work of the Association, and detailed accounts of the old and new aquarium and sea-water circulations were written by Wilson (1952, 1960).

Since 1928 there have been very considerable alterations and additions to the laboratory and, now that the major building extension has been completed, the time is opportune for a new descriptive account of the buildings and research facilities.

Various biological and environmental changes that have been observed during the present century in the area of the western English Channel are briefly described, and then theories that have been put forward to account for them discussed and compared critically with one another.

At the moment, the rise in sea temperature and a possible accompanying change in emphasis of water movements offers the best explanation of all the changes. Such a theory is obviously applicable to the replacement of coldwater northern forms by warmer-water species that has taken place in many habitats (e.g. demersal fishes, pelagic fishes, intertidal zone). A decline in number of macroplankton animals, including the pelagic young of some demersal fish, can be regarded as another aspect of the temperature change, in part related to a shift in distributional boundaries, but also influenced by the replacement of herring by pilchard, which has apparently led to increased stocks of pelagic fish, and perhaps a higher level of predation throughout the year. It is suggested that the plankton production cycle may have become slightly smoother, and possibly a little more efficient, with less' wastage' to the bottom-fauna, the biomass of which may also have suffered indirectly from the increased stocks of pelagic fish.

Three new species, Paraserpula planorbis, Omphalopoma stellata and Spirorbis sarsiae, are described and three known species are redescribed. A list is given of the Serpulidae found between 100 and 1000 fm (approx.) and an appendix gives a key to genera of the sub-families Serpulinae and Filograninae

There are three British species of the wood-boring isopod Limnoria. The boreal L. lignorum is found around all coasts, but is least common on the south and west coasts, where the temperate L. quadripunctata is dominant. The latter also occurs in the Isle of Man, Ireland and the Channel Isles, but has not been found on the east coast. The warm-water L. tripunctata is found only on the central south coast and in South Wales. Each species can survive at levels equivalent to 60-65 % exposure, but in mixed populations L. tripunctata dominates the upper level of Limnoria attack, L. quadripunctata dominates the middle zone and L. lignorum is found at the base of exposed piling or sublittorally.

Observations are described upon the innervation of striated muscles, the innervation of the slime glands, and the subcutaneous innervation in the hagfish, Myxine glutinosa L. It is shown that the two types of striated muscle fibre receive different types of motor innervation. Presumed sensory endings are described from above the striated muscle fibres of the ventral part of the body, and are similar to those endings near to the dorsal root ganglia whichcan be traced to their cells of origin within the ganglia. It is suggested that these endings are proprioceptive in function. Other endings within the outer edge of the myosepta are described, which may possibly also have a proprioceptive function. A rich plexus of neurons is described upon the capsule of the slime glands, and these neurons, like those of the subcutaneous plexus, receive pericellular terminations from the axons of central cells. It is suggested that they are motor to smooth muscle fibres, in the slime-gland plexus being related to the expulsion of slime (together with the action of striated muscle fibres), and in the subcutaneous plexus playing some role in the control of the venous blood in the subcutaneous sinuses.

The difficulty of keeping planktonic organisms alive in captivity has greatly hindered experimental studies of their physiology and behaviour. This has especially been the case with the plankton of the deep sea. Up to the present our studies of these organisms have been largely morphological and distributional and it is clear that to learn more about their ecological relationships we must find means of keeping them alive to study their metabolism and behaviour experimentally. With this end in view attempts have been made to keep some oceanic plankton animals alive in the laboratory on board ship and ashore.

It is shown that sulpholipid is the predominant acetone-insoluble lipid of grass, sphagnum moss, Selaginella, and of some blue-green, green and brown algae.

This sulpholipid is separable into three entities by paper chromatography.

Phospholipid predominates over sulpholipid in red algae, fungi and the fluffy pericarp of the broad bean.

The sulpholipid in these plant tissues gives a single spot on paper chromatogram

A relationship between sulpholipids and photosynthesis is suggested.

One of the most fundamental problems of oceanic ecology is the study of spatial and temporal changes in plankton distribution and the elucidation of the factors that govern them. A prerequisite of such work is that the tech- niques of sampling should be of sufficient accuracy to allow real changes in distribution to be detected and expressed in quantitative terms. The difficul- ties of fulfilling these sampling requirements are formidable even for the smaller plankton organisms, but a number of reliable and accurate quantitative samplers do exist for animals in this size range. For the larger zooplankton and smaller nekton, however, the lack of suitable sampling gear and methods has to a great extent restricted our knowledge. While the use of large conical nets and trawls at all depths over a wide geographic range has produced a vast body of data on the systematics of the major groups of macroplankton, there is little precise data on the depth distribution of even the commonest forms and only the vaguest estimates are available as to their relative abundance. The lack of more precise data can be attributed to two major technical deficiencies, first, the absence of efficient and reliable methods by which large nets can be opened and closed at depth, and secondly, the lack of accurate depth monitoring equipment. This paper describes the preliminary results of work aimed at meeting the first of these requirements but reference will also be made to the use of an instrument that represents a major advance towards serving the second.

The osmotic pressure and sodium concentration of the coelomic fluid of two species of httoral centipede have been measured and compared with those of a terrestrial one. A similar value of about 45 % sea water was obtained for all three species. Weight changes and longevity experiments in normal and diluted sea water suggest that littoral species are less permeable than terrestrial ones and it is suggested that the enlarged salivary glands of littoral species could be the site of salt secretion. A comparison is drawn with teleost and other examples whose body fluids are hypotonic to their environment.

In the past few years considerable attention has been paid to the distribution of the microflora of the salt marshes at Gibraltar Point, Lincolnshire (National Grid reference TF 555576). During these studies it was observed (Turner, personal communication) that blue-green algae (Myxophyceae) were of frequent occurrence in soil samples from the region, but no analyses of the algal flora were carried out. It is well established, however, that blue-green algae are generally present in salt marsh regions (Chapman, 1960 a). Previous studies on the blue-green algae of British salt marshes are few, although detailed investigations have been carried out at Canvey and Ynyslas (Carter, 1932, 1933 a, b) and Scolt Head Island (Chapman, 1939). Some difficulty is experienced, however, in attempting to correlate these results with present day studies, mainly because of the widespread colonization of salt marsh regions within recent years by Spartina townsendii H. & J. Groves, and by the fact that few quantitative data are available. It is hoped that the present communication which is concerned with the blue-green algal flora of the New Marsh at Gibraltar Point, a region dominated by Spartina townsendii, will allow an assessment to be made of the flora prevailing in a developing salt marsh under present-day conditions.

Observations have been made on living pogonophores obtained from the continental slope to the south-west of the British Isles and from the continental shelf off the west coast of Ireland.

The blood of five species examined contains haemoglobin in solution. The tube appears to be freely permeable to water, but less so to electrolytes and small molecules.

The appearance and behaviour of living embryos is noted and the spermatozoon of one species figured. Possible feeding and other behaviour is discussed and it is concluded that the best line of future investigation lies with the shallow-water forms found in the Arctic Ocean.

The sulpholipid fractions of green and brown algae were isolated by column chromatography, but attempts to repeat the preparation on red algae and fungi by the same methods were unsuccessful.

It was recently suggested (Boney & Corner, i960,1962a) that, contrary to the theory of complementary chromatic adaptation, the accessory pigment phycoerythrin might not be involved in photosynthesis by sporelings of the intertidal red alga Plumaria elegans (Bonnem) Schm. but is used primarily as a means of protecting the plant from excess green light in the wave-band 500–540 mμ. This work, however, was done with one species only, and concerning the wider question of marine red algae in general, it seemed possible that the role of phycoerythrin might vary with ecological distribution. Thus, plants completely submerged and thereby excluded from most red light would use their accessory pigments for photosynthesis (energizing chlorophyll a indirectly); but plants adapted to long periods of normal daylight would be similar to Plumaria in relying to a much greater extent on chlorophyll a alone for photosynthesis, and use their accessory pigments as protection against inhibitory green light.

The retinae of three species of deep-sea shark, Centrophorus squamosus, Centroscymnus coelolepis and Deania calcea, have been studied. All had goldencoloured photosensitive pigments, similar to those of deep-sea teleosts. The absorption maxima for the unbleached pigments lay between 472 and 484 m/n. The retina of the hake (Merluccius merluccius) was studied for comparison; its retinal pigment absorbed maximally at 495-5 mix. Some observations on the retinae of the moray eel (Muraena helena) and the Atlantic salmon (Salmo salar) are also described.

Fifteen experiments on the foraminiferid Elphidium crispum (L.) are described. They deal with feeding, movement, the substratum, and salinity, and their bearing on ecology.

The daily production of feeding cysts was used as a measure of the metabolic rate and healthiness of the foraminiferids. Phaeodactylum tricornutum, both living and dead, was used as food; a distinct preference was shown for living food. However, kaolin and graphite having a similar size to the Phaeodactylum were also accepted as food. It is suggested that E. crispum selects its food on the basis of size. The colour of the protoplasm is shown to be closely related to the pigments of the food

Movement in the horizontal plane is normally random. However, this species prefers a clean, hard substratum to one of clay; once a specimen has escaped from a clay substratum, it is loathe to return to it and therefore movement in this instance must be directed and not random.

Movement in the horizontal plane is normally random. However, this species prefers a clean, hard substratum to one of clay; once a specimen has escaped from a clay substratum, it is loathe to return to it and therefore movement in this instance must be directed and not random.

The rate of feeding is shown to be closely related to the salinity of the water, the feeding rate decreasing with the salinity. The amount of calcium present in sea water or in subsaline waters does not appear to affect the rate of feeding. However, lowered temperatures help E. crispum to survive for longer periods in subsaline water. At temperatures of 8° and 16° C , cultures survived subsaline water of 20%0 salinity for 38 days, but at a salinity of i5%03 only the culture kept at 8 C survived (for 15 days).

A series of nine plankton cruises was completed by the research ships ‘Sir Lancelot’ and ‘Platessa’ in the spring of 1954 to study the ecology of a patch of Calanus finmarchicus (Gunner.) off the north-east coast of England. This paper will deal with the problems encountered in identifying such a patch over the period from 19 March to 4 June 1954.

The cell production of sporelings of five species of marine red algae is inhibited by 3-amino-i,2,4-triazole (3AT).

Results show that short-term immersions in culture medium containing 3AT have a lasting effect on the growth of sporelings

This growth inhibitory effect is reversed by addition of adenine.

Protracted contact with 3AT results in some chlorosis of the sporeling

The growth inhibitory effects of 3AT are more marked with sporelings of intertidal red algae than with sublittoral species.

Larvae of the ascidian Styela coriacea (Alder and Hancock) were obtained by artificial fertilization and from an incubating adult. The larval cerebral vesicle has a normal otolith but no ocellus.

The analysis shows that the diatom community resides mainly in the top 2 mm of the mud and when in bright light the community moves less than 1 mm towards the surface of the estuarine mud, although the colour of the mud changes noticeably.

The fine mud supports more diatoms than the coarse mud, and the community in fine mud is nearer to the mud surface, but this is probably caused by the more rapid extinction of light in fine mud than in the coarse mud, while also large spaces between the coarse mud particles may offer less protection from the effect of tidal scour than in fine mud, this giving contributory explanation for the less abundant community in coarse mud.

Algal productive rates have rarely been estimated at sea, although many estimates have been made of primary productivity as g carbon/m2/day. A distinction may be drawn between productive rate and productivity, and it is in the use of the term ‘standing stock’. The latter is the quantity of living algal material per unit volume or beneath unit surface. The productive rate is the rate at which the standing stock reproduces itself; for a given species it is of course a division rate. It is expedient to use the term ‘division rate’ for a single species, but the term ‘productive rate’ may be used for the whole algal community. The productivity is the product of standing stock and productive rate and so contains in it the very great variations of standing stock that are the common experience of all planktologists.