This paper reports the results of a study of pollination and fertilisation in alfalfa. The experimental material consisted of plants of the Grimm variety and certain high seed-setting selections which are normally self-fertilised.

The high seed-setting types do not differ from the low seed-setting types with respect to the stage of anther dehiscence, amount and distribution of the pollen, or relative length of pistil and anthers. Anther dehiscence in both types regularly begins in the pointed bud stage and pollination is completed at the erect standard stage.

Pod-setting is shown to depend upon flower tripping. Tripped flowers set a high proportion of pods, while untripped flowers invariably wilt and drop.

The normal body temperature of the pigs used in these experiments showed an appreciably greater variability than has hitherto been considered normal for pigs, the limits being 98·3–104·80° F. and the variation is independent of environmental temperature, or season of the year. The average normal temperature of the adult hog is 101·7° F.

In fasting for from two to five days a reduction of body temperature was noted in a large majority of cases, amounting on the average to 1·7° F.

Whether the normal or fasting figures are taken, the mean body temperature is higher in youth (50 days) than in the adult hog by about 1·5° F.

1. Increase of acidity with depth, is a common feature of Nigerian soils.

2. Examples and possible explanations are given for three types of acidity increase with depth. In the first, the greater acidity is confined to the depths immediately below the surface and is possibly dependent on a permanently undisturbed vegetation. In the second, the acidity continues to increase to a certain depth below which there is a regular decrease. This is more evident on mature soils, and may be dependent on a short but intense rainfall followed by a prolonged drought. In immature soils, derived from igneous acidic rocks under alternate wet and dry seasons, the acidity increases steadily with depth into the decaying rock mass.

Stimulatory effects upon germination and growth were observed in a very wide range of dosages, upon exposing seeds and seedlings to the radiation from a radioactive mud of Hungarian origin. Emanation was not excluded, but interposed lead sheet practically abolished the significant differences. Stimulation was observed whether the seeds were placed directly in contact with, or at a little distance from, all but the largest amounts of mud. Treatment of seeds, before sowing, with the radiation from large amounts of mud for periods exceeding about 48 hours was harmful to germination and to growth; this harmful effect was more marked when the seeds were moistened.

The degree and the kind of stimulation varied with the kind of seed and its history. Wheat seeds treated with vital stains showed responses to irradiation which appeared to depend upon the stain.

The present paper reports the results of experiments which were carried out to obtain information on the types and amounts of the common foodstuffs which should be included in a ration for the prevention of avitaminosis A in swine. The actual vitamin A requirement of swine in terms of carotene was also investigated.

Ten different diets were used and three animals were placed on each. Seven of these diets produced the classical symptoms of avitaminosis A in the animals, two contained minimal or just subminimal amounts of the vitamin, while one appeared to permit storage.

The rations on which the symptoms of avitaminosis A did not appear included maize meal and alfalfa meal. Both these foodstuffs, however, have been shown to produce undesirable effects in the animals at the levels at which they must be fed to prevent the onset of the disease symptoms.

The effect which different varieties grown on small plots side by side may have upon each other is usually termed competition. Naturally if a tall variety, or one having a root system highly developed, is planted on small plots in alternation with a short variety or one with small roots, it is to be expected that the latter will suffer from the unfavourable neighbourhood, whereas the former will be benefited. In other words, when testing varieties differing in their habits of growth, etc., owing to the effect of competition some of them may appear better and others worse than they are under natural conditions.

The results of a winter nutrition experiment on dairy cows were used as a uniformity trial in order to indicate the magnitude of the standard error we may expect if a continuous treatment experiment is designed with a preliminary control period.

An initial period of three weeks is suggested, and some discussion given on the design and analysis of this type of experiment.

1. Low temperature grain pre-treatment of some varieties of wheat, barley, and oats, has resulted, in most cases, in a stimulation to early development of the plant with a modification of the juvenile habit.

2. In addition to early developmental stimulation, winter varieties of barley and wheat also showed marked acceleration in the date of earing. Spring varieties either failed to show this earing acceleration or else were but slightly affected.

3. Glasshouse culture during the first few months of growth resulted, in most varieties, in a greater response to the grain pre-treatment. It is suggested that this was due to the absence of low temperatures in the glasshouse.

The application of a principle of “differential regression”, which is of value in the statistical treatment of some types of experimental data, is illustrated. Briefly stated, the principle involves the use of a separate regression coefficient for each subclass of observations when correcting these observations for the influence of variability in a correlated variate, instead of the use of an average net regression coefficient as employed in the usual variance and covariance analysis.

1. The shape or surface form of garden and field peas may be smooth, wrinkled or dimpled, depending upon the genetic constitution. The appearance of these forms is discussed and some comments made on the manner in which the characters are transmitted and expressed.

2. The genetic formulae of the three forms as suggested by other investigators do not explain satisfactorily the results observed from numerous crossings effected by the writers.

3. The following alternative combinations are offered as forming the constitution of the commercial varieties utilised:

Experiments with sterile cultures of peas, inoculated with their appropriate strain of nodule bacteria, have given the following results:

(1) In quartz sand the rate of excretion of nitrogenous compounds from the nodules was directly proportional to the capacity of the culture flask, i.e. to the supply of air to the roots.

(2) In water cultures abundant nodules were formed within the liquid medium. However, when all nodules were submerged, the plants grew poorly and their nitrogen content was low. The growth was the better, the more the nodules were situated above the liquid surface. The submerged nodules were, however, fully capable of fixing nitrogen, since the removal of part of the liquid with the subsequent exposure of the nodules to air resulted in a profuse growth of the plants. Nevertheless, in water cultures the excretion of nitrogenous compounds from the nodules was very slight or nil. The nodule formation was completely in hibited when all air in the medium was replaced by nitrogen gas.

The efficiency of ten different strains of Rhizobium trifolii was studied with nitrogen free quartz sand cultures of red clover during three consecutive years.

(1) In the first season, distinct differences were noted in the size and nitrogen contents of the crops produced, after inoculation with ten various bacterial strains. These differences remained clearly discernible throughout the experimental period of 3 years: the individuality of the strains had not materially changed during this time.

(2) Reinoculation with the most efficient strain during the third year did not affect the plants.

(3) The loss of plants in winter was greatest in the jars which were inoculated with weak strains.

Spacing influences yield in that, beyond certain limits, the decrease in yield is proportionate to the increase in distance between the setts.

The limit to distance between the setts beyond which yield will fall varies with size of seed.

Seed size influences yield, large seed giving higher yields than small seed with the same spacing.

Size of seed influences the size of tubers produced. Small seed gives larger individual tubers than large seed with the same spacing.

Large seed possesses a greater number of sprouts per tuber than medium or small seed. Thus large seed gives rise to a greater number of true plants within the “hill”.

The greater the number of true plants in the “hill” the greater will be the number of tubers produced by the “hill” and the smaller will be their individual size.