McLean's shorter method of H2SO4-HNO3 digestion of the soil for total P2O5 failed on some red soils from Ceylon, although Hall's HC1 method gave satisfactory results. The cause of failure of the McLean method was interference by the larger quantities of various bases extracted by H2SO4-HNO3.

After first separating the total phosphoric acid as ferric phosphate, McLean's method produced results closely agreeing with those obtained by Hall's method. Total phosphates were separated by first neutralizing the acids in the soil digest and then precipitating the HC1 solutions of the neutralized product by sodium acetate and acetic acid. On boiling, all the phosphoric acid in the soil extract was separated as ferric phosphate. HNO3 solution of this ferric phosphate when precipitated in the usual way gave a clean yellow precipitate of ammonium phospho-molybdate.

H2SO4-Se served as a good substitute for H2SO4-HNO3 in soil digestions and the results obtained were substantially the same as by Hall's method or by the modified McLean's method. H2SO4-Se digestion has certain advantages, such as the possibility of determining both nitrogen and phosphoric acid on the same soil digest.

When selenium is used as catalyst and the phosphate separated by ammonium acetate and acetic acid, the HNO3 solution of total phosphates produces a white precipitate of a complex ammonium selenito-molybdate along with ammonium phospho-molybdate when precipitated by ammonium molybdate. This defect was eliminated after replacing ammonium acetate by sodium acetate.

Attention is drawn to the unexpected behaviour of selenium compounds of phosphoric acid formed during soil digestion towards the reagents used for precipitating total phosphates.

1. With insemination of approximately 2 billion sperms, pregnancy resulted from inseminations up to 6 days prior to ovulation, but not when inseminations were made earlier, or on the day after ovulation.

2. Ovulation was induced in one mare by injecting pregnancy urine extract when a large follicle was present in one ovary, although the mare remained anoestrous, as judged by vaginal and cervical secretions. This mare became pregnant from an insemination 2 days prior to the induced ovulation.

1. Field experiments on the use of cut ware setts with the potato varieties Arran Banner, King Edward and Majestic have shown that with proper handling no loss in plant establishment need result. When the cut setts are planted at the same distances as whole setts, there is liable to be a reduction in the yield per acre because of the lower yield per plant, but the actual rate of increase may be increased considerably by cutting because of the larger number of plants obtainable.

2. No benefit has been found from the practice of dusting the cut surfaces of tubers of Majestic with slag, lime or ashes, while adverse effects resulted from the use of a fungicide and alum.

3. The exposure of cut setts to drying conditions lowers their resistance to attacks by micro-organisms, and encourages the breakdown of the tuber flesh by bacteria of the carotovorum group.

4. In general, the use of certain fungicides, either directly on the cut surface, or as a means of moistening sack coverings, is not to be recommended because of the adverse effects of the fungicide on the natural resistance of the live tissue of the tuber flesh.

In an experiment with twenty-four Large White pigs fattened from weaning to bacon weight on a diet containing either 5 or 9% of dried Clostridium residues the latter was found to be an efficient protein supplement.

The authors wish to express their thanks to Dr S. J. Rowland who made all the chemical analyses involved, to the Directors of Commercial Solvents G.B., Ltd., who kindly supplied the product, and to Mr E. Gill, Works Manager of the above Company, for helpful collaboration.

1. A filter apparatus cannot be relied upon to give a correct reading of the suction of soil water when this exceeds about 400 cm. of water.

2. Owing to the contribution of dissolved matter to the freezing-point depression the suction in a soil of normal low salt content can only be obtained from the freezing-point depression with reasonable accuracy when it exceeds about 4000 cm. of water (freezing-point depression greater than 0–3° C).

3. Suctions in the range 400 to 4000 cm. have been measured with the aid of calibrated absorbers consisting of thin plates of Portland stone.

4. The plates were calibrated up to 1000 cm. by the application of suction through a filter, and above 1000 cm. by measuring the vapour-pressure depression by a new technique.

5. When applied direct to soil, the new vapour-pressure technique is more reliable than the freezing-point method, and can be applied to materials which do not exhibit a well-defined freezing-point.

6. A suitable soil was washed free from salts and brought to 1000 cm. suction on a filter. Measurements of the vapour-pressure depression and the freezing-point depression checked well with the thermodynamic formulae.

1. Growing young sugar-beet plants under continuous illumination before transplanting into the field induced stem elongation and anthesis in considerably greater proportions than in plants not exposed to continuous light exposure.

2. The technique of growing young plants under continuous light exposure during the winter offers a means of rapid multiplication of small seed stocks, and also of isolating the various physiological types comprising the population. In particular, the technique should make it possible to select types resistant to bolting.

3. Analysis of the glomerule populations obtained from the plants showing anthesis at definite dates indicates that there is a definite trend in the proportions of large, medium and small glomerules as the season progresses.

Experiments on the effect of inter-row cultivation of sugar beet, carried out in the three years 1939–41 on a sandy loam, led to the following results:

1. If the soil nutrients are in short supply hoeing or hand-weeding increases the yield of the beet, provided these operations are carried out before or shortly after singling.

2. Hoeing is more effective than hand-weeding, but it cannot yet be said with certainty whether this is due entirely to more efficient weed destruction, or whether there is some additional effect, such as mulching.

3. If adequate quantities of soil nutrients are present, inter-row cultivation has little effect on yield, and the crop can tolerate a considerable weed infestation without any effect on yield.

The results for sugar beet on the heavy clay-with-flints soil at Rothamsted show:

1. Additional hoeings after singling, above a modest minimum, have either no effect on yield or else depress it.

2. On the one occasion when pre-singling cultivations were given, the yield was increased.

3. In contrast with the Woburn results the effect of cultivation does not vary with, the level of manuring.

The influence upon milk production of changes in level of feeding and in proportion of bulky foods has been investigated, using all available experimental material.

The experimental results show that increases in level of feeding, to rates well in excess of conventional English standards, are capable of giving substantial increases in milk production (Fig. 1).

It is shown that physiological efficiency falls off as food intake is increased. A curve representing physiological efficiency has been constructed by taking account of changes in live weight as well as changes in yield of milk (Fig. 4).

1. The average electrode potentials of laboratory silages of various types have been measured.

2. The electrode potentials of ordinary and molassed silages tended to assume values of the order of –0·05 to –0·10 V. from about the third day; the pH of these silages lay in the range pH 4·0 to 5·5.

3. In a number of instances secondary increases of electrode potential were observed, frequently in association with secondary deterioration.

4. The electrode potential of silage prepared with hydrochloric acid and of pH 3·4 remained steady around +0·18 V.; the potential of silage prepared with formic acid and of pH 3·9 was about + 0·35 V. initially but declined towards + 0·23 V. at 35 days.

5. Curves for the ‘pure’ carotene content of laboratory silages displayed minima during the early stages of fermentation except in the case of formic acid silage.

Several cases of ergot in barley encountered in 1941 have been investigated, and records have been examined of the occurrence of ergot in cereal crops in this country during the past 24 years. These indicate that ergot is found more frequently on rye than on wheat, barley or oat, this, in descending order, being their relative susceptibility. A more detailed examination of records of the occurrence on rye in the seasons 1939–42 indicates that the disease is more prevalent in northern districts than elsewhere; of 500 acres of rye surveyed in Suffolk and Norfolk in 1942 only three crops comprising 80 acres showed a trace of ergot. It is rare on both wheat and barley and little is known as to the susceptibility of their varieties, although on several occasions it has been noted on Rivet wheat, and has been recorded on Rivet and Triticum vulgare crosses. In this country there is no record of it having been found on oat, apart from the one specimen found in a field of mixed corn in Cambridgeshire.