The pectic acids formed on saponification of lemon-peel pectins C and L have been fractionated by graded precipitation with sodium acetate. The results of analytical and electrophoretic studies on the pectic acid fractions have been interpreted as being typical of those of the fractionation of chemically homogeneous polydisperse systems. Similar fractionations of lucerne polysaccharides have indicated the presence of a single component in pectic acid A and of two components in pectic acid B. The nature of polysaccharide heterogeneity in pectic acid preparations is discussed.