During a visit to the Leyden Museum last September I was able to examine several species of birds, which had not come under my notice during the preparation of the 7th volume of the »Catalogue of Birds”. Some of the species proved to be very distinct and I greatly regret that they have been omitted from the volume or relegated to foot-notes, as being of doubtful validity. During the whole of the time that this volume was going through the press, I was engaged in the moving of the Zoological Collections from Bloomsbury to South Kensington, and was unable to get abroad for my accustomed course of study in foreign Museums. I am sensible that the value of this volume has been somewhat impaired by these omissions, and I publish these supplementary notes, in order to supply descriptions of several species which are wanting to its pages. Ale the diademata (Bp.), Sharpe, 1. c. p. 58. Turdus diadematus, Temm. MSS. in Mus. Lugd., undè Bessonornis diadematus, Bp. Consp. I, p. 302.