In the account of “Pining” in sheep given by McGowan(1) there are so many points of similarity, both in the symptoms and in the general environmental conditions under which the disease is developed, with the disease known in New Zealand as “Bush-sickness,” as to suggest that these two diseases may be of a similar nature.

On the arid, sparse, phosphorus deficient pasture of the Vryburg district of the Cape Province, grading up of scrub cattle, by combining the introduction of pure bred bulls with the feeding of bone meal to the cows, is attended with great success so far as shown by the first crossing. Remarkable differences in favour of the mineral supplement are shown, in respect to reduced mortality incidence, increased fertility of cows, and superior development of calves.

Determination of the phosphorus partition in blood is described, combining dry combustion with the ceruleo-molybdate procedure of Deniges. Advantages in speed and convenience are claimed over the conventional Briggs methods.

Data are recorded concerning the phosphorus partition of the blood of cattle grazing over phosphorus deficient pasture of the Union of South Africa. The outstanding characteristic is low inorganic phosphorus, with a correlated reduction in total phosphorus.

When a small ration of bone meal is given to the cattle, comparatively normal figures are shown. Heifers approaching two years in age, supplied with bone meal from weaning onwards, show a normal inorganic P fraction of 5 mg. per 100 c.c. of blood. Control heifers without bone meal show 2·3 mg., or less than half. Control cows may drop to 1 mg., or even lower. Calves of control mothers are normal so long as milk supply is adequate, but may show reduced inorganic P if aphosphorosis of the mother is acute. In general, low inorganic P in the blood is associated, with poor condition of the animal. Rapid colorimetric determination of inorganic P in the blood of the grazing animal, easily obtained from the jugular vein, provides a simple means of detecting phosphorus deficiency in the pasture.

Although long-continued phosphorus deficiency leads to the clinically recognisable disease “Styfsiekte,” especially in lactating animals, the less pronounced deficiency, manifested as malnutrition and stunting of growth, without direct mortality, is detected by blood analysis with equal certainty.

In the paper “Minimum Mineral Requirements in Cattle,” by Theiler, Green and du Toit (1927), analytical data concerning the mineral constituents of the blood of a calf, born of a cow suffering from aphosphorosis, were recorded, but left over for later consideration.

An unknown phosphorus fraction previously recorded by the authors as frequently present in calf blood, is shown to be nucleoprotein and due to the presence of precursors of fully mature erythrocytes. The same fraction may also appear in small amounts in human blood and in horse blood, and always occurs in very large amount in the nucleated erythrocytes of birds.

In regard to phosphorus partition, the same general relationship holds between the blood of lambs and of the mother ewes, as between the blood of calves and the mother cows. Total phosphorus is about twice as high in lamb blood as in maternal blood, inorganic phosphorus about twice as high, and organic acid-soluble phosphorus about three times as high. A considerable proportion of an acid-insoluble phosphorus fraction, probably nuclein, may be present in the red corpuscles of lamb blood and may even be present in foetal blood. The organic acid-soluble fraction is confined to the corpuscles, both in young blood and adult blood, but i n one case of a six-month calf foetus a small proportion was noted in plasma.

In cases of anaemia in cattle and sheep, of infectious origin, parasitic origin, or due to simple haemorrhage, the phosphorus partition of the blood reveals an “unknown fraction,” confined to the corpuscles, and evidently nucleoprotein. It is determined by difference between the total phosphorus and the sum of total acid-soluble and lipoid phosphorus. It is associated with the appearance of nucleated red cells (normoblasts and Jolly bodies) and vanishes as they disappear. The amount may make up a considerable proportion of the total P.

The new observations of Haines on the pressure deficiency of liquid in a soil-like aggregate confirm the theoretical deduction that the pressure deficiency falls off with increasing water content, but do not justify his belief in a high static stress as saturation is approached.

A theorem is established connecting the static stress at any water content with the pressure deficiency and the dry area of the surface. This, together with general considerations of the energy conditions of physical equilibria, appears to dispose of the two assumptions from which the high values for the cohesive stress at saturation have been deduced.

It has been known for many years that agricultural grasses become less nutritious as they approach maturity and ripen their seed. The grass plant in its earlier weeks of growth makes a heavier draft on soil nitrogen than later in the season, with the result that its tissues are particularly rich in protein. As the grass continues to grow, the protein, now formed in lessening quantities, is distributed throughout a greater bulk of the plant and thus its percentage in the dry matter is reduced. From a study of the analytical data on record of grasses examined at several stages of growth, it may be summarised that as a grass matures the protein, ash, fat and water decrease while the carbohydrates (nitrogen-free extract) and fibre increase. Further, in addition to the larger percentage in their dry matter of protein and mineral constituents, the leaves and shoots of very young grass are more succulent, palatable and digestible than the leaves of the older plant. These facts have been used in giving advice as to the best period at which to cut for hay, i.e. the stage of growth at which the grass will yield the largest amount of digestible matter per acre. This will vary somewhat with different species, but the weight of scientific evidence is in favour of cutting at or shortly after the flowering period. It will thus be seen that chemistry has contributed valuable information in relation to the best time or period for the harvesting of grass for hay.

(1) Digestibility trials with wheats, carried out with White Leghorn cockerels, indicate that “weak” and “strong” wheats are equally suitable as sources of supply of food nutrients for poultry.

(2) In the production of wheat for poultry feeding, yield rather than strength should be the primary aim of the grower.

(3) Further research work on the Katayama method of estimating the digestibility of poultry feedingstufls is indicated.

(1) Digestibility trials with “whole” maize and “flaked” maize indicate that steam cooking by commercial processes considerably increases the digestibility of the food nutrients in maize. (2) The view held that the fowl is akin to the pig so far as its powers of digestibility of low fibre foods are concerned is substantiated by the results of the trials here reported.

From the results presented it may be permissible to point out the following:

Fungi are responsible for the fixation of very small quantities of nitrogen, while the Azotobacter and B. amylobacter groups are the important nitrogen fixers in the soil.

B. amylobacter is able to fix from 4 to 5 mg. of nitrogen per gm. of dextrose consumed.

B. amylobacter has an optimum range of pH. between 6·0 and 7·0, and Azotobacter between 7·0 and 8·4.

Azotobacter utilises the organic acids produced during the fermentation of dextrose as sources of energy for nitrogen fixation in the absence of dextrose. B. amylobacler does not, or does only to a limited extent, utilise such products.

Large quantities of dextrose do not favour an efficient nitrogen fixation, as large quantities of the organic acids produced effect the reaction of the media rendering the organisms inactive.

The nitrogen fixing organisms seem to be equally well represented in the heavy and light soils.

(1) The possibility of using acetic acid as a reagent for extracting exchangeable calcium from carbonate-free soils is discussed, and experimental results are given showing that calcium is quantitatively precipitated from an acetic acid medium.

(2) A method for determining exchangeable calcium using 0·5 N acetic acid is described, and figures are given comparing this proposed method with the Hissink method.

(3) A modification of the proposed method is suggested in the case of heavy clay soils owing to the impervious nature of these soils which probably does not allow the acid to penetrate through the whole mass of the soil when leached on the filter paper.

In a previous paper Quinlan(1) published the results of his observations on a flock of sheep which had been vasectomised for two years. The present paper contains a résumé of the data already published, to which an additional twelve months' observations have been added. This paper gives the data available from observations carried out on the flock over a period covering three years, or a period of time which allowed full skeletal development to take place.

1. The interaction of Bordeaux mixture with lead arsenate and with calcium arsenate has been studied by an examination of the effects which are produced:

(a) When hydrated lime is added to the arsenical compounds.

(b) When copper sulphate is added to the arsenical compounds and hydrated lime.

2. The nature of the interaction of calcium hydroxide and diplumbic hydrogen arsenate has been shown to be most complex and to result in the complete decomposition of part of the lead arsenate and th e formation of basic calcium arsenates.

3. Support is not given to the view that calcium carbonate decomposes diplumbic hydrogen arsenate with the production of soluble arsenic compounds.

4. When the lead arsenate, in water, is allowed to interact for long periods with excess of hydrated lime, the amount of basic calcium arsenates formed is such that large quantities of arsenic are brought into solution by the action of carbon dioxide.

5. Under conditions when the calcium hydroxide is rapidly converted to the carbonate the amount of arsenic rendered soluble is slight.

6. The conclusion is formed that in actual spraying there is a definite reduction of the risk of arsenical injury when hydrated lime is added to lead arsenate and to calcium arsenate.

7. It is concluded that when the conditions are such that the addition of hydrated lime brings about a reduction of arsenical injury, the use of an “equal-lime” Bordeaux mixture containing an equivalent amount of calcium hydroxide will prove far more effective.

1. The formation of colloidal CaHPO4 by the interaction of CaCl2 and Na2HPO4 in the presence of neutral casemates has been demonstrated.

2. The colloidal CaHPO4 is shown to be non-diffusible across a membrane of cellophane.

3. A theory is outlined which will account for the secretion of the high concentrations of calcium and phosphorus in milk from the low concentrations of these elements in the blood.

Four years ago one of us(1) propounded a method of computing rations for all classes of farm animals on the basis of a maintenance ration related to the animal's live-weight plus a production ration estimated in accordance with the amount and kind of product—such as live-weight increase, work, milk—which the animal is expected to produce. This method is on the same lines as the modern method of computing rations for milch cows which is based on Kellner's work (2). It has been used in practice for the last four years and has been found to be successful, not only as a practical method of computing rations, but more especially as a logical and intelligible method of teaching students. For this latter purpose it is a great advance over the learning of standard rations since it appeals rather to the reasoning powers than to the memory. In view of these considerations, the method has been incorporated in Rations for Livestock (3). Much of the time of the Staff of the Cambridge Animal Nutrition Institute has been devoted, during the last four years, to investigations designed to fill the gaps in our knowledge of the basal metabolism, the maintenance requirement, and the production requirement of farm animals.

The respective effect of the period of lactation and the age of the cow on the yield and quality of the milk have previously been studied separately (see J. Agric. Sci. 17, PtI, p. 118, “The Influence of the Stage of Lactation and the Breed of the Cow on the Yield and Quality of the Milk,” and 17, Pt III, p. 420, “The Influence of the Age of the Cow on the Yield and Quality of the Milk”), and an analysis of the data has now been made with regard to the joint influence of these factors.

A practical adaptation of a method devised by Miss Glynne for testing indoors the immunity or susceptibility of potato varieties to wart disease is described. The method consists of infecting by summer sporangia the young sprouts of the tubers under test. Extensive test has given such satisfactory results that there is little doubt that the method is infallible.

The writer wishes to render his grateful thanks to Mrs N. McDermott, who has been actively associated with him throughout the work described and who is largely responsible for the technique employed; to Miss M. D. Glynne, of the Rothamsted Experimental Station, for her many helpful suggestions; to Mr W. H. Parker, Director of the National Institute of Agricultural Botany, Cambridge, for his assistance and advice; t o Dr R. N. Salaman for supplying material for test, and to Dr G. H. Pethybridge for his kindness in examining tubers sent to him.

It is generally recognised that the study of arid soils frequently necessitates sampling to a depth of 6 feet or more. The most satisfactory way of doing this is to dig a pit and take samples from a vertical face. This method is obviously unsuitable for the examination of small plots and some kind of boring tool must be used instead. In the tenacious clay soil of this area hand augers have been tried without success, but the mechanical difficulties involved have been largely overcome by use of the apparatus illustrated, which (a) secures a truly vertical bore, (b) resolves the thrust into two components.