THE methionine content of cereals and legumes widely used in India has been measured. Determinations were made with a Lumetron photo-electric colorimeter using the sodium nitroprusside method of McCarthy and Sullivan1 as modified by Csonka and Denton2, and further modified by us3. The values shown in the accompanying table give the mean of at least two determinations. It is seen that the vetch pea is very poor in methionine content. The relationship between this very low methionine content of the vetch pea and lathyrism has been discussed elsewhere. There is evidence to support our view that lathyrism is due to absolute methionine deficiency, aided by some toxic substance which further brings about a disturbance in methionine metabolism. It is also apparent that the low nutritive value of lentil protein is due not to cystine deficiency but to methionine deficiency. The better quality of rice protein is due, at least in part, to the much higher methionine content of the former. Further investigation is in progress.