MANY strains of Lancefield group A streptococci synthesize a starch-like polysaccharide when grown on a medium containing maltose or maltose-polymers1, and some of these strains also produce an extracellular amylase2. It has been shown that amylase-negative starch-accumulating strains are associated with acute glomerulonephritis and acute rheumatic fever3. There is as yet no direct proof that the starch itself is more than a metabolic marker of bacterial variants, but because of the possibility of its production in vivo its isolation and characterization were of considerable interest, for it has been shown that bacterial polysaccharides of high molecular weight may have long persistence in the tissues4.