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Butyrivibrio sp. C3 degrades rutin anaerobically to yield phloroglucinol, carbon dioxide, 3,4-dihydroxy-benzaldehyde, and 3,4-dihydroxyphenylacetic acid. The sugars are first released by intracellular glycosidases and then the heterocyclic ring of the aglycone undergoes hydrolytic cleavage. The glycosides of quercetin added to the medium are readily metabolized, but the aglycone is not.

The effect on the conversion of carbon14 to quercetin by a buckwheat plant caused by variation in the dose rate of a carbon 14-labelled precursor in μmoles over a 100-fold range has been studied. The results expressed as dilution of carbon14 varied over a 200-fold range for the same precursor with most of the variation being found at low dose rates. When expressed as the percentage of administered carbon14 converted to quercetin the results for acetate, D-glucose, and L-phenyllactic acid were mostly constant over this range but L-phenylalanine had a maximum percentage conversion or an optimal dose rate. An explanation of the results in metabolic terms has been attempted.It is recommended that the "percentage of C14 converted" be used to express results in plant biosynthetic work.

An account has been given of observations made for over two years on the composition of the milk of the breeds of goat distributed throughout Great Britain. The average percentages of fat and solids-not-fat in the milk of the breeds, together with their standard errors, are recorded. The frequency with which evening and morning samples fell within specified limits of these constituents is indicated for each breed, and diagrammatically for all goats. Detailed analyses of the milk of each breed are given, with the maximum and minimum values encountered and the standard errors of the average figures. Comparison is made of the composition of the milk of the goat with that of the cow. The effect of stage of lactation on yield of milk and on percentages of fat and solids-not-fat are shown by means of curves. the effect of age on the yield and composition of milk is indicated. The average yields per lactation for each breed, based upon the records of animals officially recorded during the last ten years are noted.

Various C14-labelled compounds were administered to Fagopyrum tataricum. After allowing 24 hours for metabolism the quercetin was isolated and degraded, by a modified alkaline fusion, into phloroglucinol (ring A) and protocatechuic acid (ring B plus carbon 2). Uniformly labelled sucrose or C14O2 (assimilated photosynthetically) formed quercetin equally labelled in the A and B rings, but sodium acetate-1-C14 (or acetate-2-C14) gave quercetin labelled almost entirely in ring A. Isotope competition experiments indicated meso-inositol and phloroglucinol were not precursors of ring A. The biosynthesis of quercetin from C14O2 or acetate required the combined action of stem and leaves. Light was not required for synthesis of quercetin from acetate.

The results discussed in this paper are based on the weights and composition of the excrements of eight pullets, fed for the periods stated on three rations, which differed only in the amounts of calcium and phosphorus supplied in various combinations. The total amounts of calcium and phosphorus supplied daily were approximately the same in all cases.The birds were 5 months old White Wyandottes, and increased considerably in weight during the experimental period. No eggs were laid, but Pullet No. 2 died of prolapsus of the oviduct, and was found to have seven nearly full-sized yolks and one unshelled egg in the oviduct.

An account has been given of the lipin, phytin and inorganic phosphorus, and of the protein and non-protein nitrogen present in the wheat plant, from seven weeks before ear emergence until the crop was harvestedThe percentages and amounts of phosphorus and nitrogen so combined, together with their distribution between straw and ear, have been discussed.Relationships between phytin phosphorus and protein nitrogen, and between lipin phosphorus and non-protein nitrogen, have been indicated.

Cuttings of Fagopyrum tataricum were allowed to metabolize various labelled compounds for 24 hours in the light. Quercetin was then isolated and degraded by alkaline hydrolysis of its pentamethyl ether into veratric acid (ring B plus carbon 2) and 2′-hydroxy-2,4′,6′-trimethoxyacetophenone (ring A plus carbons 3 and 4). Eleven amino acids, including tyrosine, were poor precursors of quercetin as were also protocatechuic acid and p-hydroxybenzoic acid. Shikimic acid, phenylalanine, p-hydroxycinnamic acid, and cinnamic acid were very good precursors followed by (in decreasing order of effectiveness) caffeic acid (fair), sinapic acid, m-methoxycinnamic acid, and ferulic acid (very poor). Quercetin formed from β- or ring-labelled cinnamic acid gave labelled veratric acid on degradation, and that from α- or carboxyl-labelled cinnamic acid gave labelled 2′-hydroxy-2,4′,6′-trimethoxyacetophenone. Two-ninths of the activity of quercetin formed from uniformly labelled phenylalanine was found in the acetophenone derivative and seven-ninths in the veratric acid. These results show that C6.C3 compounds are used with the carbon skeleton unchanged for the synthesis of ring B and carbons 2, 3, and 4 of quercetin and that the ring hydroxylation pattern of the compound used determines its effectiveness. None of the compounds were good precursors of ring A.

The use of lime and phosphates in reclaiming heather moorland was investigated in two experiments. Large initial dressings of hme resulted in a rapid rise in pH. An initial dressing of 9 tons CaCO3/ac resulted in a more rapid rise to pH 6 than did 6 tons/ac and the soil was maintained above pH 6 for a longer period. Three annual dressings of 3 tons/ac gave a slower rise in pH and a longer period above pH 6. Split treatments, half before and half after the first ploughing, gave no long–term advantage where a programme of pioneer cropping was being followed. Basic slag and North African phosphate were as effective as superphosphate for root crops at low pH values. Basic slag was as effective as superphosphate for grassland establishment and gave a greater rise in soil phosphate. North African phosphate was virtually worthless as a source of phosphate for establishing grasses and clovers, and gave a negligible rise in soil phosphate. Given adequate supphes of lime and phosphate, frequent small apphcations of N over the first 2 or 3 years are vital to the success of a reclamation programme under the conditions described.

1. An account has been given of the percentages of nutrients in the dry matter and weights of nutrients in tops, tubers and roots of potato plants throughout growth under six fertilizer treatments.2. Manurial treatment affected dry-matter content of tops but not of tubers.3. Balanced manuring, as represented by N2PK treatment, resulted in tubers in which nitrogen content of dry matter declined with age. The effect of the K was to lower the nitrogen, phosphorus and calcium contents, to increase chlorine content of all parts of the plant, and to maintain a much higher and more constant concentration of potassium in tops and roots. With unbalanced manuring the nitrogen content of the tubers was more constant.4. Manuring with nitrogen only raised the content of potassium in the dry matter of all parts of the plant.5. Nitrogenous manuring, whether alone or in combination, raised the nitrogen content of the dry matter of all parts of the plant, a smaller proportion of which was present as protein. Calcium and chlorine contents were lowered.6. Phosphate manuring in conjunction with nitrogen depressed the concentration of potash in the dry matter of all parts of the plant.7. N2P plants were the first to attain their maximum uptake of all nutrients, namely, about 7 weeks from appearance above ground, at which time N2PK plants had absorbed only 40% of the quantities finally noted.8. No losses of elements were observed in the plants which received balanced manuring (N2PK), but losses of calcium and chlorine occurred in all other plants, amounting on the average to 25 and 37% respectively, but being highest in N2P plants. A significant loss of potassium occurred in N2 plants and a highly suggestive loss of phosphorus occurred in N2P plants.

1. An account has been given of the composition and weights of nutrients in 3200 wheat plants from seven weeks before ear emergence until the crop was harvested. The distribution of the plant nutrients, and the rate of assimilation and translocation of these nutrients, have been discussed. 2. In the case of the whole plant, the percentage of nutrients in the dry matter decreased from the time of the first sampling, with the exception of silica, which had a tendency to remain constant throughout. In the case of the ear, diminution in the percentage of nutrients in the dry matter was observed from a fortnight after ear emergence until harvest. 3. Marked increases in the weights of all nutrients in the whole plant were noted until ear emergence, from then onwards assimilation was much slower. The plant attained its maximum quantities of the nutrients in the following order: potash seven weeks, lime and chlorine five weeks, nitrogen three weeks, carbon, phosphoric acid and silica two weeks, before harvest. Assimilation of these had, therefore, ceased at the above stated times, although transference to the ear proceeded until within about a week before harvest.