1. A mixture of sand and bentonite (after converting it to the calcium clay), containing 6 per cent, by weight of the latter, was found to be a suitable medium in pot cultures for the growth of grass. A good sward of perennial rye grass was established in the medium by suitable watering, manuring and cutting of the grass, within 11 weeks of sowing.

2. The mixture allowed of easy control of the moisture content, and appeared to possess a moisture-retaining capacity comparable with that of a natural soil.

3. The mixture is almost totally deficient in both nitrogen and phosphoric acid, and markedly deficient in potash and in some of the less common elements necessary for plant growth.

4. In view of the above properties and of the buffering action due to the presence of the bentonite, the mixture would appear to be suited to the more general study in pot culture of plant nutrition problems, and to offer several important advantages over either sand alone or natural soil for this purpose.

1. B. mycoides is an organism which energetically decomposes organic nitrogenous matter forming large amounts of ammonia. When soil was inoculated with a culture of this organism, active ammonification took place and the rate of nitrification was raised.

2. The first effects of the inoculation of soil by B. mycoides were a parallel development of ammonification and nitrification; later the rate of ammonification fell off, but nitrifying organisms continued to transform ammonia into nitrate.

3. The degree of nitrification in chernosiom soils is a function of the activity of B. mycoides. By creating conditions appropriate to these bacteria, both ammonifying and nitrifying processes are likewise intensified.

4. Fertilisation with dung is beneficial not solely on account of the nutrients supplied ad hoc, but also because it leads to an increase in the numbers of B. mycoides. Farmyard manure is a source of B. mycoides, and acts similarly to an inoculation with those bacteria.

1. A method for the weekly determination of the amount of hair produced on defined areas of skin is described.

2. The normal hair growth in adult male and female guinea-pigs has been determined. It is shown that the amount of hair produced on a defined area of skin in equal intervals of time is not constant. The fluctuations are mainly due to variations in the number of follicles which are active.

3. There seem to be two periods during the year when an increased production occurs in most animals, in late spring and autumn. The times of increased hair growth correspond approximately to the occurrence of the moult.

4. Measurements have been made of the length of the fibres at the end of a week's growth. It is found that fibres of all lengths are present and that the maximum length at the end of any week in any stage of the cycle is 5 mm.

The effect of pregnancy on hair growth and shedding in the short-haired guinea-pig has been studied. It is shown that during pregnancy the amount of hair produced on defined areas of skin decreases until at the time of parturition and for 2 weeks afterwards practically no hair growth is taking place. This is followed by an increased output of hair substance, and hair production returns to its normal level after 11 weeks.

1. Sexual periodicity in many animals is largely conditioned by variations in the daily light period. That egg production in hens may be controlled by the use of artificial lights has long been known.

2. The action of light is probably connected with the activity of the anterior lobe of the pituitary.

3. The natural variation in daily light period at different latitudes has been used to study the effect of light on egg production throughout the world. Curves have been constructed of egg production grouped in 5° of latitude and the correlation with the hours of daylight at those latitudes studied.

The main object of the present investigation (season 1932) has been to secure as much information as possible concerning yield, composition and nutritive value from crops of lucerne already established in several different localities. This work may be considered as preliminary to the more systematic investigations which have been designed to begin in the season 1933.

The 1932 investigation comprised work on the following crops: (1) 4-year-old lucerne (variety Provence) grown on the Howe Hill University Farm at Cambridge. (2) 1-year-old lucerne (variety Provence) grown at Willingham, Cambridgeshire. (3) 1-year-old lucerne (variety Hungarian) grown on the Gravel Hill University Farm, Cambridge. (4) 4-year-old lucerne (variety Provence) grown at Tunstall, Suffolk. The season was characterised by its cold, wet, late spring and the prevalence of droughty conditions in June.

Recent work on the growth of wool in relation to the cystine supply in the sheep's diet, together with the discovery in proteins of a new sulphur-containing amino acid, methionine, has directed attention to the importance of being able to determine, by methods easily and quickly carried out, the amounts of total and inorganic sulphur in plant products and feeding stuffs. Details are given in the present note of the methods employed by the writers for the estimation of total sulphur, sulphate sulphur and, by difference, organic sulphur.

In order to disentangle the various causes affecting foetal growth, and so the birth weight of the animal, it is necessary to employ statistical methods in addition to physiological ones. This paper presents methods suited to a study of growth where two such factors have to be separated and their effects on growth measured quantitively.

Data from the laboratory examination of fleece samples from representative animals of the parental Border Leicester and Cheviot stock, the F1 “half-breds” and the F2 ewes, are submitted.

The characters of mean fibre length, fineness and mean fibre volume are discussed, the variability found in the various types being particularly noted. The distributions of fibre lengths are also considered, it being found that all the parental forms also appear in the succeeding generations.

Evidence of blending inheritance is not manifest in the results, which support the interpretation of multiple factors as responsible for the expression of the wool characters of length and fineness.

Attention is called to the importance of considering fibre volumes as criteria of follicle activity.