The Marine Biological Association of the United Kingdom, to whom the Plymouth Laboratory belongs, is a corporate body of subscribing members, interested in scientific investigations concerning the habits and life-histories of food fishes and other marine animals. The Laboratory is managed by a Council elected annually by the members of the Association.

The following list brings up to date a previous publication and has been classified, so far as practicable, according to subjects, in order that it may be useful for purposes of reference. The list does not include publications recording the results of observations made on material supplied by the Association to workers in different parts of the country, of which a considerable amount is sent out each year.

Results are given of a further series of collections made with the stramin ring-trawl to determine the diurnal behaviour of post-larval stages of Teleostean fishes in the Plymouth area.

The catches were very satisfactory and showed that in no case, except for Clupeids and Gobies, was there any really marked movement of young fish towards the surface. This confirms previous observations.

It has been shown on this and previous occasions that Clupeids are many times more abundant in the catches at night than in the daytime, and any study of their seasonal or horizontal distribution would probably.have to be carried out at night.

For the remaining species, except perhaps Gobies and Callionymus, oblique hauls taken either at day or at night should give a fair picture of seasonal or horizontal distribution. More observations are, however, required.

The association of the whiting young with the medusa, Cyanea capillata, is discussed.

The small individuals were examined before the height of the breeding season, and there is a probability that many or most of the indeterminate individuals would become male. Hermaphrodite individuals have been observed previously, and in certain samples 10% of the males contain doubtful young ova in the gonad. It is therefore concluded that Patella vulgata is apparently a protandric hermaphrodite, but that the evidence is not yet sufficiently good to prove protandry.

It is suggested that possibly two kinds of male, which may be recognisable by chromosome constitution, may occur, one being pure male and one protandric, and also that sex-change may be controlled by as yet unknown metabolic conditions.

The breeding period is discussed ; it may extend from August to March at Plymouth in different seasons, and spawning may occur within this period. A maximum of spawning appears to occur about January-February. The conditions controlling breeding and spawning in Patella are unknown, and as the course of seasonal shell-growth is unknown, although shell-growth is general at the end of the breeding season, it is suggested that research on the subjects in the future should be combined.

Many common limpets Patella vulgata, settled and grew on the cement piles of a new wharf constructed at Plymouth. Each pile or part of this wharf provided experimental material for the determination of the maximum age of the limpets which grew thereon, as the dates of completion were known. It was found that at an age of about one year limpets grew to lengths of 26 to 35 mm. in 1912, and to at least 11 to 27 mm. in 1913 :and at an age of two years to at least 53 mm. in 1911-1913, and to 47-49 mm. in 1912-1914.

The shells were of the mid-tide-level type, and were low, broad, and rather thin. It is considered that such growth in length is unusual, and is correlated with the habitat and favourable climatic conditions. In the same situation in 1913 marked limpets grew from January 27 to September 2, respectively, 20 mm. (from 21 to 41) and 15 mm. (from 38 to 53), and showed arrest of growth in midsummer.

Other marked limpets showed arrest of growth in the winter period, and many at lengths of about 25 mm. an arrest of growth independent of any season of growth. Seasonal shell-growth is discussed briefly ; a postbreeding shell-growing period is general in spring and early summer, but it is not known whether a midsummer resting-period is general among individuals more than one year old. Ad hoc investigations are suggested in combination with work on sex and spawning.

A preliminary notice is given of investigations into the cause of variation in shell-height, wherein it is shown that shell-height is determined probably entirely by the degree of exposure of limpets to desiccation, in such a manner that the drier the habitat the higher the shell is. Limpets submerged at neap tides have a relatively uniformly low shell, those exposed at high-water neaps have a relatively high shell, which is higher in the drier than in the damper situations, apparently irrespective of exposure to wave-action.