The amino‐acids of several grassland species, cereals and bracken

Various species of plants have been sampled at different stages of first and second growth from field crops and from special plots; the proteins have been extracted and hydrolysed and the amino‐acids separated by two‐dimensional chromatography on paper. Fourteen amino‐acids have been determined colorimetrically and the proportions of the acids have been found to be affected by such factors as stage of growth, season, nitrogenous fertilizers and species. Several consistent changes, particularly in arginine, lysine and glutamic acid, have been recorded and attention has been directed to the difficulty of comparing plant proteins without a knowledge of the conditions in which the plants have been grown and sampled.