Concentrations of Zn have been determined in the tissues of normal lobsters from sea water containing about 5μg/1. of Zn. The blood usually contains about 6 μg/g of Zn, mostly in the serum, while the soft tissues contain between 10 and 50 μg/g. Long exposure to sea water containing 100/μg.g/l. of Zn fails to alter the Zn concentrations of the blood, muscle and gonads, but increases the levels in the urine, excretory organs, hepatopancreas and gills. This result suggests that extra Zn is absorbed from high Zn sea water, possibly via the gills, and that two methods by which this is removed from circulation are by urinary excretion and absorption by the hepatopancreas.

Changes in the blood Zn concentration produced by injection are rectified quite rapidly in the same way. Injections failed to change the Zn concentrations of muscle and gonads.

Further experiments showed that Zn can be absorbed rapidly from the stomach and reaches the blood partly at least via the hepatopancreas. Again, this extra Zn is removed from the blood by urinary excretion and by absorption in the hepatopancreas. Eventual removal of Zn in the hepatopancreas probably takes place via the blood and excretory organs rather than via the gut. The role of the gills and gut in the regulation of the body Zn content has not yet been studied.

By comparing the two species of Amphiura in controlled, directional bottom current flows, clear differences of behaviour can be demonstrated. These differences have been shown to be associated with two quite distinct feeding methods. Amphiura filiformis holds the arms up into the current flow with a rheotactic response to current direction and feeds by trapping both non-living particulate suspended matter and phytoplankton. Amphiura chiajei does not show this response and feeds exclusively on deposited matter on the sediment surface. Both species have modifications of the podia associated with the different methods of feeding. Estimates of growth rate, longevity and oxygen uptake suggest that Amphiura filiformis is a rapidly growing species with a high metabolic rate and food requirement, whereas Amphiura chiajei is slow growing and long-lived with a low metabolic rate. The environmental requirements of the two species are discussed.

Experiments reported in a previous paper have indicated a considerable water loss by isolated preparations of the tube feet of Asterias rubens when ligatured in the protracted state. Because of its specialized structure, the podial diameter remains constant throughout the stepping cycle and this simplifies the procedure for measuring the surface area. Measurements of the internal hydrostatic pressure within the tube foot ampulla systems shows a maximum of about 30 cm water to be reached during the protraction phase of the stepping cycle, falling to nearly zero during the resting period. From these data it is possible to calculate a value for the permeability to water of the tube foot membrane, and such a value is compared with other membranes.

By measurement of the total area of protracted tube foot membrane exposed by the animal when supporting itself in sea water, it is possible to arrive at a figure for the total water loss by the water vascular system. For a 50 g animal this amounts to some 0·5 ml./h. Experiments involving blocking or extirpating the madreporite, and with isolated arms, make it extremely improbable that this loss could be made good from this route.

As alternative mechanisms, a slight hypertonicity due to the presence of excess potassium, or water movement as a direct consequence of the operation of an ion pump are discussed. In view of the hydrostatic pressure within the water vascular system the possibility of its functioning as a physiological kidney is also discussed. A possible alternative function for the madreporite is put forward.

Measurements of cephalothorax length were made on the females of five species of oceanic copepods for the period from January 1958 through August 1959. The seasonal length variations of the three species of Pleuromamma (P. piseki, P. abdominalis and P. xiphias) followed the cycle in total phytoplankton. Significant positive correlations were obtained between the mean lengths of P. abdominalis and P. piseki and the mean quantity of phytoplankton of the month previous to sampling, but there was no correlation between length and temperature.

The seasonal length variations of females of Haloptilus longicornis and Lucicutia flavicornis differed in pattern from that of the Pleuromamma species and no correlation was found between their mean lengths and the annual cycles of phytoplankton or temperature. These species may feed selectively on some possibly unmeasured fraction of the plankton or on particulate organic matter.

Previous work has shown that in waters with a wide temperature range there is a high negative correlation between length and temperature and no correlation between length and phytoplankton. In other regions with an intermediate temperature range the sizes of successive generations of copepods are correlated to almost equal degree with the temperature and the quantity of phytoplankton available during growth. In the Sargasso Sea, where there is a narrow temperature range but a definite seasonal cycle in total phytoplankton, the length variations of the Pleuromamma species are correlated with the phytoplankton cycle and not with temperature.

Laminariocolax tomentosoides is a common epi-endophyte on the I.O.M. Though probably pseudoperennial as an endophyte it produces fertile external filaments only from September to June with a March maximum in size and numbers. It reproduces vegetatively by growing through its host's tissues and asexually by means of zoospores from plurilocular sporangia. In culture, zoospores give rise to fertile plants in 7 days and several generations can be produced in 4 weeks. The offspring bear only plurilocular sporangia. The chromosome number is apparently 16 and the life-history probably a postponed series of diplonts.

Laminariocolax tomentosoides produces cysts which, in the past, have been mistakenly identified as unilocular sporangia and which are so similar to the ascocysts of Ascocyclus that this genus would seem to be based on a character of little value. Another description of unilocular sporangia in the species is tentatively attributed to infection by a fungus.

Analyses have been made of some of the constituents of the coastal sea water and the river water, and the results have been correlated with the growth phases of some planktonic diatom species and littoral epiphytes, although for most species the sea-water temperature and light intensity were limiting factors.

The factor determining the death of an epiphytic diatom community in the littoral zone has been considered to be the air temperature in conjunction with desiccation and a summary of the limiting temperatures for each of the four substrata is given in Table 7. Table 10 is a summary of all the distribution and temperature records. The heat itself is not lethal in many cases but the desiccation of the epiphyte in the littoral zone is accelerated at higher temperatures. Diatoms in damp situations were found to occur at temperatures which in a dry site were limiting, and further work indicating the relationship between relative humidity and lethal temperatures is needed.

The ability of a diatom to survive depends upon the water-retaining ability of the substratum. Chalk and large algae favoured the growth of most solitary epiphytes, and filamentous epiphytes grew particularly well on algae except the filamentous Navicula, which were best suited by chalk. The Achnanthes blue-green community was most frequent on wood. Concrete makes a firm substratum and allows rapid growth in winter but it is easily dried and most diatoms on it are destroyed in the summer.

Four diatom genera (Fragilaria, Grammatophora, Biddulphia and Melosira) are able to exist in the epiphyte flora and the shore plankton and the term facultative epiphyte is suggested to describe the behaviour of at least some of the species of these genera.

Five cyphonautes are described in Nordisches Plankton (Lohmann, 1911). Cyphonautes schneideri and C. borealis are larvae of Membranipora membranacea and represent extremes of variation in the shape of the shell. Cyphonautes balticus, like C. compressus which was very inadequately described, is the larva of Electra pilosa. The cyphonautes of these two species are the only ones likely to be encountered in the plankton of normally saline European seas. Cyphonautes barroisi is the larva of the brackish-water Electra crustulenta.

Cyphonautes balticus Thorson (1946), not Lohmann, is the larva of M. membranacea.

Larval synonymies for M. membranacea and E. pilosa are given.

The use of the Cyphonautes names is undesirable, and those of the polyzoan adults should be employed.

As part of the programme of study of the geology of the western approaches initiated at Bristol by Prof. W. F. Whittard (Whittard, 1962) information has been accumulated concerning the distribution and nature of the metamorphic rocks exposed in a series of inliers between Start Point in the east and Dodman Point in the west.

Early dredgings in this area were described by Worth (1908). Six core samples and two dredgings of metamorphic rocks are listed by Hill & King (1953). Mica schist in situ is recorded by Holme (1953). Various cruises in R.V. ‘Sarsia’ from 1957 onwards have yielded seventeen cores and further dredged samples. Additional material, collected from the exposed parts of the Eddystone reefs or obtained by diving at critical localities, has become available through the kindness of members of the staff of the Marine Biological Laboratory at Plymouth.

Sixteen cores and eight dredged samples serve to demarcate an area of schistose rocks, extending some 24 miles from east to west and 7 miles in maximum width from north to south, off the southernmost part of Devon (Fig. 1). These rocks, with an exception to be noted, compare closely with those exposed on land, between Bolt Tail and Start Point, south of a well defined east-west boundary (Ussher, 1904; Tilley, 1923). There are examples of quartz-muscovite-chlorite schists precisely like the Start Mica-schists and Bolt Mica-schists described by Tilley. Albite porphyroblasts, in a rock dredged near East Rutts (Fig. I, 1262) which is transitional to Tilley's ‘schists of composite origin’, show well the contorted swarms of carbonaceous inclusions which he describes (1923, p. 180).

Meiobenthos, here defined as metazoans passing through a ½ mm screen, is described from core samples collected on muddy grounds at 100-140 m depth in the North Sea and off the west coast of Scotland between February 1962 and August 1963.

Sixteen cores of 2·2 cm diameter were collected from Loch Nevis, and 14 from the Fladen ground. The top 7 cm of each core was passed through a 500μ then a 76μ screen. The residues were examined entire, and the nitrate of the finest mesh was subsampled.

The fauna consisted mainly of nematodes, kinorhynchs, ostracods, copepods, polychaetes, and lamellibranchs. Between 61 and 97 % of the population consisted of nematodes, but copepods were second in importance and were more abundant than recorded on other subtidal grounds.

The fine mesh (76μ) retained almost all specimens of every animal group except Nematoda. Numerically 38% of the nematode population passed through the fine sieve, but this represented only 18% by weight.

The mean dry weight of meiobenthos on Fladen was calculated as 0·76 g/m2 and the average number of individuals was 196 × 104/m2.

In Loch Nevis the corresponding weight was 1·28 g and the number 101 × 104. The loch had a larger and more varied population of all groups except nematodes, which were particularly abundant on Fladen.

The data do not indicate significant population fluctuations throughout the year in the permanent meiobenthos.

Compared with other subtidal grounds Nevis and Fladen seem to support much richer populations, and the high values for Fladen are of particular interest since this is a poor macrobenthos area.

An attempt is made to indicate the possible level of meiobenthos productivity and it is suggested that there may be competition between meio- and macrobenthos for available organic matter which could result in a less efficient production of fish food.

Freezing-point measurements were made of blood samples taken from specimens of the marine wood-boring isopod Limnoria that had been exposed to sea water of various salinities for 2-3 days. Most of the work was done with L. (L.) tripunctata Menzies, but some preliminary experiements were carried out with L. (L.) lignorum (Rathke) and L. (L.) quadripunctata Holthuis.

It was found that the freezing point of the blood averaged 0·17°C above that of the external of medium in both hyp- and hyperosmotic environments. In the absence of any obvious factor which could explain this discrepancy, it is assumed that Limnoria has a certain degree of control over its blood concentrations.

Further experiments showed that the blood concentration fell as soon as the animal was introduced to the reduced salinity and levelled off at the hyperosmotic value within a few hours. There was some evidence of a periodicity in the osmoregulation.

The possible energetics of osmoregulation in Limnoria are discussed and it is concluded that the amount of energy utilized in the process is unlikely to make any significant inroad into the energy resources available for boring activity.

Total fat, carotenoids, and vitamin A were determined physicochemically in sixty-nine species and fifteen generic groups of pelagic marine copepods.

Vitamin A was definitely present in Euchirella curticauda and Gaetanus kruppi and possibly so in Gaetanus pileatus and in a sample of Gaetanus spp. No vitamin A activity for vitamin A-depleted rats was found in fractions from a lipid extract of 1854 g of Calanus finmarchicus.

The significance of these findings is considered in relation to the high vitamin A reserves in many fish preying upon pelagic copepods.

The original distinction between the Gadiculus populations of the east Atlantic and the Mediterranean was made on the basis of differences in pigmentation and vertebral count found in the larvae. A comparison of adult fish from the two areas shows that there are significant differences in body dimensions and also in certain meristic characters, particularly vertebral count. These differences are briefly discussed.

The oxygen uptake of eggs and larvae of Norwegian herring from Bergen (mean unfertilized egg dry weight about 035 mg) and of Baltic herring from Kiel (mean unfertilized egg dry weight about 0·10 mg) was measured by a reference diver and a Warburg respirometer. Anaesthetized Kiel larvae had values of about 0·10μl./larva/h and Bergen larvae 0·25μl./larva/h. When expressed as Qo (μl./mg dry weight/h) the values became Kiel 2·3, Bergen 2·5.

Oxygen uptake of embryos before hatching and of larvae, expressed as Qo, was most affected by activity, increasing in very active organisms by five to ten times the resting value of 1-2 μl./mg dry weight/h. Experiments to test the effects of temperature and salinity were done using anaesthetized larvae in some cases.

Temperature experiments with larvae gave a Q10 of about 2, the Qo, of anaesthetized Kiel larvae ranging from about 2·0 at 50° C to 35 at 14°C, and that of unanaesthetized Bergen larvae from 2·5 at 6° C to 50 at 140°C.

Eggs and larvae of both races reared in salinities from 5 to 50 %0 showed no detectable difference in oxygen uptake. However, abrupt transfer of anaesthetized larvae from one salinity to another caused violent fluctuations (by up to ten times) before adaptation took place. Buoyancy differences appeared to mask differences in oxygen uptake of unanaesthetized larvae in similar transfer experiments.

There was little tendency for oxygen uptake to become reduced during darkness in either Bergen or Kiel larvae.

The effect of age on oxygen uptake (expressed as Qo) was not marked, though there tended to be a peak at, and just after, hatching, with a tendency for a fall off during starvation.

The hitherto unknown hydroid of the anthomedusa Bougainvillia pyramidata has been found in the Firth of Clyde, and medusae from it have been reared to maturity. The hydroid and the stages of development of the medusa are described and figured, and the species is compared with B. ramosa. The seasonal occurrence and distribution of the medusa are discussed.

The hydroid Bougainvillia muscoides (M. Sars) has also been found in the Firth of Clyde. Medusae have been reared from it, and a description, with figures, of the stages of development is given. The specimens found in 1901 in this area and described by Browne as Thamnitis sp. are shown to be young medusae of B. muscoides. The geographical and bathymetric distribution of the species and the seasonal occurrence of the medusa are described and discussed.

The Council have to report with regret the deaths of Captain V. Lord, a member of the Association's staff for 28 years and well known to many workers at the laboratory as skipper of S.S. ‘Salpa’; and of Cdr. C. A. Hoodless, D.S.C., R.N.R. who was Master of R.V. ‘Sabella’ from 1948 to 1953 when he was appointed Master of the Association's new research vessel ‘Sarsia’. Cdr. Hoodless was an able and skilful seaman and did much for marine science. His burial took place at sea from R.V. ‘Sarsia’ on 16 March 1964.

The Council record with great pleasure the award of the 1963 Nobel Prize for Physiology and Medicine to Prof. A. L. Hodgkin, F.R.S., and Prof. A. F. Huxley, F.R.S. Both have been visiting research workers at the Plymouth laboratory and Prof. Hodgkin has served many times on the Council of the Association.

The Council and Officers

During the year Major E. G. Christie-Miller resigned from his position as a Representative Governor on the Council of the Association since 1941. Major Christie-Miller gave devoted service to the Association as Honorary Treasurer from 1941 to 1956, and had been a Vice-President since 1951.

Col. Sir John Carew Pole, Bt., D.S.O., T.D., has been nominated by the Fishmongers' Company in his place.

Four ordinary meetings of the Council were held during the year, two in the rooms of the Royal Society, one in the rooms of the Linnean Society and one at Plymouth. At these the average attendance was seventeen.