HoME VII THE TREASON OF ISENGARD, chapter VI, The Council of Elrond (1), p. 132 (et p. 138 pour le contenu de la note 28)
"For Saruman the [Grey )] White is as you know the greatest among us, and was chief of the White Council. Radagast the Grey [in pencil > Brown] is of course a master of shapes and changes of hue,(27) and has much lore of beast, bird, and herb; but Saruman has long studied the works of the Enemy to defeat him, and the lore of rings was his especial knowledge. The last of the 19 rings he had....(28)
note 28 : "28. I cannot make out the two concluding words, though the first might be 'gathered'. But whatever the words are, the meaning is clearly that Saruman had acquired the last of the Rings - and wore it on his finger, as appears subsequently in this text (cf. FR p. 271). - In the last text of 'Ancient History' that has been given Gandalf refers to the discussion of the Rings at the White Council, and to those who 'go in for such things'; see p. 22."