Littorina (Melarhaphe) neritoides (Montagu) is stated by Tattersall to be viviparous. Living usually above high-water mark, often with Littorina saxatilis (L. rudis in Plymouth Marine Fauna 1931, Marine Biological Association), it would seem at first sight that free-swimming larvæ would be useless. L. saxatilis is truly viviparous and provided with a special pouch for its young which crawl out as small individuals similar to the parent. Tattersall (1908, 1909, 1920) when he discovered the planktonic egg-capsules of L. littorea (Caullery and Pelseneer (1910) having described them at almost exactly the same time) then regarded L. neritoides as viviparous. He has, however, kindly sent me the statement given below. Following him many workers have also declared that this species is viviparous (Flatteley and Walton, 1922, Colman 1933 Russell, 1934 and others). It is now possible to show that, not only is it not viviparous but it lays planktonic capsules very similar to those of L. littorea.

Attention was first drawn by Wilson (1932) to the large copepod fauna which can be found in an ordinary sandy beach. In his introduction he describes his method of collecting these copepods (p. 7) and in the course of the paper describes a number of new genera and species thus obtained.

Sand-dwelling animals, particularly Crustacea and worms (excluding sessile forms), are usually regarded as burrowers, since in their migrations they displace the particles of their environment. The fauna opened up by Wilson's discovery is of a quite different type. In contrast to true sand-burrowing animals, these copepods do not displace the particles of the sand through which they move but crawl over the surface of the grains, which, by capillarity, always hold more or less water, even high up on the beach at low tide. Such copepods, together with nematodes, rotifers, protozoa and other animals sufficiently small, may be regarded as part of an “interstitial” fauna.

1. For the preservation of ropes the importance of the preservative against bacterial decay being also an internal lubricant for the rope fibres must be remembered.

2. Tests have been carried out for one year in sea-water, which was much contaminated by sewage at times, under Plymouth Pier and in cleaner water of a tidal basin outside Plymouth Sound Breakwater for 10½ months, using 2-inch and 0-6-inch ropes respectively; the latter was manila, the former were manila, hemp, sisal and coir.

3. The preservatives included cutch, cutch bichromate, cutch ammonia copper sulphate, coal tar distillates, including those of the Coalite process, also hardwood and softwood tars. The tars and tar oils were tried alone and mixed with copper soaps, naphthenate (Cuprinol and Shell products), oleate and resinate, also zinc and iron naphthenates (Cuprinol). The naphthenates and oleate are good lubricants.

4. Very good results were obtained with green Cuprinol containing tar and with 10 per cent copper oleate in a light coal tar; slightly inferior were 10 per cent copper resinate in Coalite heavy oil or in creosote oil as now used largely in Plymouth; also 10 per cent copper oleate with 20 per cent of Coalite tar in Coalite neutral oil, b.p. 100–245° C, which i s a very cheap solvent. All these maintained the thin manila rope at or above 70 per cent of its initial strength after 10½ months; the untreated control was down to 13 per cent.

Vertical hauls between surface and 45 metres depth were made with a measuring net, throughout 1934, at a position 5 miles S.W. of Plymouth Breakwater in circa 50 metres depth of water.

The phytoplankton organisms were counted and also assessed from their content of plant pigments.

A close relation was found between numbers of diatoms and their pigment contents after making allowance for the small size of three species.

The phosphorus content of the phytoplankton was estimated on several occasions.

The zooplankton organisms per cubic metre of sea were counted and estimations were made of their phosphorus content.

The diatom population differed from that found in 1933, in which year the spring outburst was shorter but more intense, the sporadic summer outbursts were more intense, the autumn one lasted longer; and more phosphate was utilised by the plants during the first half of the year.

1. Monthly samples of Echinocardium cordatum were taken at Port Erin in 1932,1933 and 1934, and at intervals at Fairlie Sands in the Clyde.

2. Growth is continuous throughout the year with the exception of February-March. In their first winter the young urchins attain a length of about 10 mm. at Millport and 15–20 mm. at Port Erin. In their second winter they are about 20 mm. at Millport, and 30–35 mm. at Port Erin.

4. The year 1931 was cold and produced a very small brood of young urchins; 1932 and 1933 were warm years and produced very large broods.

5. The young settle below low water and migrate into the interval zone after an interval of four to twelve months.

6. The gonads of the young urchins mature in their second year. Spawning takes place in June–July–August.

7. The nutritive bodies in the ovaries are shown to be derived from the disintegration of relict ova.

From experiments in the sea with wire cages and boxes with perforated zinc sides and tops more than 100 individuals of certain Crustacea which had grown inside the apparatus have been obtained at various subsequent dates.

Minimal mean rates of growth are obtainable from the difference between maximum size at immediate entry and size at a given later date, and the approximate age by an allowance for age at entry plus the maximum time occupiable in the experimental apparatus. It was found that C. maenas spawned early in the year may attain a carapace width of 30 to 40 mm. by the following winter. In experiments extending over twelve months from July to July male C. maenas attained a carapace width of 43 to 53 mm. and females 37 mm. at an estimated maximum age of 15 months.

A seasonal variation is found in the ovaries of immature hake (Merlucius merluccius L.).

There appears to be a seasonal change in the rate at which young eggs are formed from resting oocytes, as indicated (1) by the change in the relative abundance of nuclei in synapsis, and (2) by the change in the average diameter of the eggs in the egg-stock in the ovary. These processes show considerable correspondence in their season of incidence with the ovarian cycle of the mature and adolescent fish.

A physiological rhythm has now been detected in both somatic tissues and gonad in the immature hake, which foreshadows the physiological rhythm associated with the spawning cycle in the mature hake. The implication of this on the question of the formation of “growth-rings” in the skeletal structures is briefly discussed.

A Great number of variations from the normal type have occurred in Gammarus chevreuxi during the course of the work carried out from 1912 until now.

In reviewing these variations it is convenient to class them according to the parts affected :

(1) Pigmentation of the body (3, p. 194).

(2) The Red retinal pigment of the eye (4, pp. 45–52).

(3) The Black retinal pigment of the eye.

(4) The white accessory pigment of the eye (2, p. 350).

(5) The structure of the eye, involving also the structure of the head (1, p. 274 ; 6, pp. 356–369).

1. The barnacles at five localities in the Plymouth area were examined as a check on the general application of observations made previously i n the Isle of Man.

2. The numbers and weights per square metre, and the mean individual weights, are given for a series of tidal levels for each locality.

3. The two “clean-water” localities agree substantially with the Isle of Man, except for the presence here of Chthamalus stellatus.

4. At the three localities where the water is rich in suspended matter first Chthamalus and then Balanus decreases progressively in numbers, but the latter increases very greatly in size, especially at low water.

5. The increased growth rate at low water, where food is abundant, is compared with the similar effect observed in wave-exposed conditions in the Isle of Man.

In 1929 the Marine Biological Association began a survey of the River Tees Estuary, to study the various physical and chemical conditions and the types and distribution of animal and plant life. At the same time a tidal stream survey was carried out by the Hydrographic Department of the Admiralty. Later, for purposes of comparison, the scope of the enquiry was extended to a survey of the Kiver Tay, but on a less extensive scale.