The influence of rainfall during the growing season on the yield of the Park Grass plots at Rothamsted, which are cut for hay every year, has been investigated.

The average yields in the period 1858–1902 on the thirteen plots examined were from 18 cwt./acre on an unmanured plot to 61 cwt./acre on a plot receiving a complete fertilizer including a heavy dressing of nitrogen. All the plots showed some deterioration in yield. The effect of the total amount of rainfall from 5 March to 8 July was very substantial on all plots, the average increase in yield for each additional inch of rain varying between 0·7 and 2·4 cwt./acre; the benefit was greatest on the plots dressed with sulphate of ammonia. The rainfall effects reached a maximum in the latter part of April and early May, but the distribution of the rain appeared to be of relatively small importance.

The extent of the change in pH on incubation, when bull sperm were suspended in various fluids of different composition, was affected by the buffer capacity, the pH, and the glucose content. In one such fluid, used to replace seminal fluid, there was a highly significant positive correlation between the pH. change and the number and motility of the sperm, and between the pH change in this fluid and in undiluted semen. The various conditions which appear to affect the increase in acidity are discussed, and it is concluded that there is no practical object in determining the change in pH on incubation in an artificial fluid of uniform and constant composition, instead of in semen.

1. In studying the factors influencing the ‘easily reducible’ manganese in soils, results were obtained to indicate that the estimation is dependent on the pH of the system, the nature of the salt solution, the nature of the reducing agent and the time of contact, in addition to the amount and nature of the higher oxides of manganese present.

2. Pyrolusite (MnO2) and a synthetic preparation of manganite hydroxide are ‘easily reducible’ oxides, while manganite (MnO(OH)) and naturally occurring hausmannite (Mn Mn2O4) are apparently ‘difficultly reducible’ forms.

3. Since pyrolusite occurs in the easily reducible fraction, those deficient soils which contain only a small proportion of their manganese in the easily reducible form must contain the larger part in a form less reactive than pyrolusite.

1. Polycarboxylic and hydroxycarboxylic acids as well as pyrophosphoric acid form complexes with manganic manganese which are soluble over a wide pH range.

2. It is suggested that such complex formation may be of importance in maintaining manganese in an available form in soils.

The apparatus is a simplification and an improvement on one devised by the author for the study of soil metabolism (Lees & Quastel, 1944) Its function is to percolate a column of sieved soil automatically and regularly with small quantities of a well-aerated solution of metabolites and to return the percolated solution, now modified by the activities of the soil microflora, to the reservoir whence it came As this circulatory process is continuous, metabolic activities in the soil are reflected as chemical changes in the reservoir solution and can be followed by analyses of it.

1. A method of moderate accuracy suitable for the routine determination of potash on a large scale is described.

2. Certain minor alterations in the method of precipitation by Lewis & Marmoy are suggested.

3. Di-sodium monohydrogen phosphate is suggested as a solvent for the cobaltinitrite precipitate before the permanganate titration, thereby simplifying previous volumetric procedures.

The writer wishes to express his indebtedness to the Director of Malacca Rubber Plantations for permission to publish this work. Acknowledgement is also made of the routine work so loyally carried out by his Asiatic staff in the development of the method, especially Messrs Warrior and Thamboo, who were chiefly responsible.

1. A large-scale experiment with 274 dairy cows has been carried out to determine whether urea can be a substitute for part of the protein requirement of the lactating. dairy cow.

2. It has been emphasized that any proteinsparing effect of urea or other sources of non-protein nitrogen can only be determined in the proteindeficient animal and one of the experimental treatments was therefore designed to supply well below that minimum requirement of protein compatible with milk production.

3. The addition of protein to such a ration increasing the percentage of crude protein in the production rations from 12·9 to 17·9 and the protein equivalent from 9·5 to 14·5 resulted in a significant increase in milk production. This gave ample confirmation of the protein deficiency of the low protein ration.

Seven experiments are reported in which iodinated casein was fed to pigs. The daily doses varied from 0·25 to 1·5 g. of iodinated casein per pig daily for periods of several weeks. While the higher doses adversely affected the rate of growth of the pigs, the smaller doses were not sufficiently effective to have any practical importance.

The thyroid glands of the pigs receiving the iodinated casein appeared to be slightly smaller in size, but their histological picture was not affected.

1. The aneurin content of samples of whole oat grain representing six commonly used varieties grown in different districts in Scotland and Wales did not vary widely and there were no appreciable varietal or geographical differences.

2. There was a significant positive correlation between aneurin and protein content (r = 0·42).

3. During the growth of the oat plant from the flowering stage a steady storage of aneurin in the kernels was observed until the crop was harvested, and there was a simultaneous decrease in the aneurin content of the dry matter of the hulls, leaves and straw, suggesting a translocation of aneurin from the leaves to the kernels during the maturation of the plant.

Although the usefulness of the flying bent (Molinia coerulea) as a grazing plant is admitted by all hill shepherds and by those technical workers who are interested in moorland swards, the amount of precise information available concerning its feeding value and composition is very scanty. Since the work of Kinch (1884) done more than 60 years ago, and involving no more than a single analysis, very little attention has been given to this plant. Evans (1927) studied Molinia as a component of bog hay, and found it to be a very good source of protein, but to contain less ash than certain other moorland species, e.g. common bent, rushes, and sheep's fescue.

1. The compositions of unthreshed and threshed Northern Irish ryegrass hay as saved for seed are given and compared with published values for firstyear seeds hay low in clover and average first-year seeds hay.

2. The results of digestibility trials with samples of unthreshed and threshed ryegrass and crested dogstail hays as saved for seed are reported. It is suggested that perennial ryegrass hay as saved for seed (unthreshed) may have a starch equivalent in the neighbourhood of 23% less than that of average first-year seeds hay low in clover, and that threshed hay may have a starch equivalent of the order of 15% less than that of the unthreshed hay. There are good grounds, therefore, for the poor reputation of threshed hay among stock feeders.

1. The recommencement of the sexual rhythm from deep anoestrus, is described in barren pony mares. Follicular development and oestrus follow after an interval of preliminary changes in the ovaries and accessory reproductive organs.

2. The onset of oestrus can be accelerated by general irradiation with strong artificial light. Local irradiation with a mercury vapour lamp has no effect on the ovaries.

3. Pregnant matings will result from such artificially induced heat periods provided that ovulation is induced.

4. Doses of less than 10 c.c. of sperm injected will cause fertilization when ovulation is so induced.

5. There is a close connexion between the shedding of the coat and renewed ovarian activity.

6. The stimulus to the ovaries probably passes through the eyes as in the ferret.

Respiratory activity of ejaculated bovine semen was studied in the presence of phosphate buffer (pH 7·4), egg-yolk medium or media containing different fractions isolated from the egg-yolk.

Seminal plasma from centrifuged bull semen has very little respiratory activity as compared with whole semen. The main factor affecting the respiratory activity of the semen is the concentration of active spermatozoa, but the respiratory activity is not directly proportional to the concentration of spermatozoa, since it falls off with reduction of concentration.

Kale silage was made in five large silos and the losses of dry matter and kale constituents determined.

The losses of dry matter averaged 33%, of N-free extract 41% and of crude protein 34%.

The percentage losses are higher than with wellmade grass silage, but, nevertheless, the yields of silage (and animal nutrients) per acre compare very favourably with those of other crops, including grass.

Inclusion of straw in kale silage did not reduce losses of dry matter; it merely reduced slightly the quantity of water lost.

The present communication deals with the results of an inquiry into the possibility of utilizing dried penicillin felt, a by-product of the manufacture of penicillin, in the feeding of livestock. The availability of this by-product on a suitable scale afforded an opportunity of obtaining information about the digestibility and biological value of a mould protein. During the course of the investigation, digestion trials with both sheep and pigs, and a farm-scale feeding trial with bacon pigs, have been carried out.